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1

New Bedford Harbor Superfund Project, Acushnet River Estuary engineering feasibility study of dredging and dredged-material disposal alternatives. Report 3. Characterization and elutriate testing of Acushnet River Estuary sediment. Technical report, August 1985-March 1988  

SciTech Connect

Several of the alternatives being considered for the New Bedford Harbor Superfund Project involve dredging of contaminated sediment from the Acushnet River Estuary and placement of the contaminated dredged material in confined disposal areas. Evaluation of these alternatives requires testing sediment from the site to determine chemical and physical characteristics, settling properties, contaminant releases for various migration pathways, and treatment requirements for disposal area effluent. The purpose of this report is to describe the estuary composite sediment sample and the hot-spot-sediment sample tested at the US Army Engineer Waterways Experiment Station as part of the US Army Corps of Engineers' Acushnet River Estuary Engineering Feasibility Study of Dredging and Dredged Material Disposal Alternatives. Bulk sediment chemistry, physical characteristics, and elutriate testing for the sediments are included.

Averett, D.E.

1989-03-01

2

New Bedford Harbor Superfund Project, Acushnet River Estuary engineering feasibility study of dredging and dredged-material disposal alternatives. Report 3. Characterization and elutriate testing of Acushnet River Estuary sediment. Technical report, August 1985March 1988  

Microsoft Academic Search

Several of the alternatives being considered for the New Bedford Harbor Superfund Project involve dredging of contaminated sediment from the Acushnet River Estuary and placement of the contaminated dredged material in confined disposal areas. Evaluation of these alternatives requires testing sediment from the site to determine chemical and physical characteristics, settling properties, contaminant releases for various migration pathways, and treatment

Averett

1989-01-01

3

The Deschutes Estuary Restoration Feasibility Study: development of a process-based morphological model  

Microsoft Academic Search

Continual sediment accumulation in Capitol Lake since the damming of the Deschutes River in 1951 has altered the initial morphology of the basin. As part of the Deschutes River Estuary Restoration Feasibility Study, the United States Geological Survey (USGS) is modeling how tidal and storm processes will influence the river, lake and lower Budd Inlet should estuary restoration occur. Understanding

Douglas George; Guy Gelfenbaum; Giles Lesser; Bob Barnard; Steven Morrison

4

estuaries.  

National Technical Information Service (NTIS)

Need for a more comprehensive understanding of estuaries and their surroundings and the lack of an adequate means to exchange information concerning estuarine research stimulated the organization of the Conference on Estuaries, held at Jekyll Island, Geor...

G. H. Lauff

1967-01-01

5

New Bedford Harbor Superfund Project Acushnet River estuary engineering feasibility study of dredging and dredged-material disposal alternatives. Report 10. Evaluation of dredging and dredging control technologies. Technical report, August 1985-March 1988  

SciTech Connect

This report presents the results of an evaluation of dredging equipment and techniques for removal of highly contaminated sediments from the upper estuary of the Acushnet River, a portion of the New Bedford Harbor Superfund Project. Site conditions as related to dredge selection and operation, factors considered in selection of equipment, various dredge types considered for use, and operational procedures and controls for sediment resuspension during dredging are described. Each of the dredge types is ranked according to the following criteria: compatibility for full-scale cleanup, availability, safety, potential for sediment resuspension, maneuverability, cleanup precision, cost and production flexibility, required water depth for operation, ability to access the site, and compatibility with disposal options.

Palermo, M.R.; Pankow, V.R.

1988-11-01

6

Estuaries  

NSDL National Science Digital Library

An estuary is a body of water that is created when freshwater from rives and streams flows into the saltwater of an ocean. To understand this mixing of fresh and salt water, learners go through several activities: 1) in Salt and Water, learners dissolve salt crystals in water to observe their effects on water; 2) in Making a Salt Wedge, learners make a model of a salt wedge estuary, which occurs in nature when the mouth of a river flows directly into seawater; 3) in Plant Dehydration learners observe the effects of salinity (salt content in the water) on live plants. Includes a wrap-up guide for group discussions.

Jersey, New; Center, Liberty S.; Coalition, New J.

2006-01-01

7

Restoration of Hydrodynamic and Hydrologic Processes in the Chinook River Estuary, Washington – Feasibility Assessment  

SciTech Connect

A hydrodynamic and hydrologic modeling analysis was conducted to evaluate the feasibility of restoring natural estuarine functions and tidal marine wetlands habitat in the Chinook River estuary, located near the mouth of the Columbia River in Washington. The reduction in salmonid populations is attributable primarily to the construction of a Highway 101 overpass across the mouth of the Chinook River in the early 1920s with a tide gate under the overpass. This construction, which was designed to eliminate tidal action in the estuary, has impeded the upstream passage of salmonids. The goal of the Chinook River Restoration Project is to restore tidal functions through the estuary, by removing the tide gate at the mouth of the river, filling drainage ditches, restoring tidal swales, and reforesting riparian areas. The hydrologic model (HEC-HMS) was used to compute Chinook River and tributary inflows for use as input to the hydrodynamic model at the project area boundary. The hydrodynamic model (RMA-10) was used to generate information on water levels, velocities, salinity, and inundation during both normal tides and 100-year storm conditions under existing conditions and under the restoration alternatives. The RMA-10 model was extended well upstream of the normal tidal flats into the watershed domain to correctly simulate flooding anddrainage with tidal effects included, using the wetting and drying schemes. The major conclusion of the hydrologic and hydrodynamic modeling study was that restoration of the tidal functions in the Chinook River estuary would be feasible through opening or removal of the tide gate. Implementation of the preferred alternative (removal of the tide gate, restoration of the channel under Hwy 101 to a 200-foot width, and construction of an internal levee inside the project area) would provide the required restorations benefits (inundation, habitat, velocities, and salinity penetration, etc.) and meet flood protection requirements. The alternative design included design of storage such that relatively little difference in the drainage or inundation upstream of Chinook River Valley Road would occur as a result of the proposed restoration activities.

Khangaonkar, Tarang P.; Breithaupt, Stephen A.; Kristanovich, Felix C.

2006-01-01

8

Restoration of Hydrodynamic and Hydrologic Processes in the Chinook River Estuary, Washington – Feasibility Assessment  

SciTech Connect

A hydrodynamic and hydrologic modeling analysis was conducted to evaluate the feasibility of restoring natural estuarine functions and tidal marine wetlands habitat in the Chinook River estuary, located near the mouth of the Columbia River in Washington. The reduction in salmonid populations is attributable primarily to the construction of a Highway 101 overpass across the mouth of the Chinook River in the early 1920s with a tide gate under the overpass. This construction, which was designed to eliminate tidal action in the estuary, has impeded the upstream passage of salmonids. The goal of the Chinook River Restoration Project is to restore tidal functions through the estuary, by removing the tide gate at the mouth of the river, filling drainage ditches, restoring tidal swales, and reforesting riparian areas. The hydrologic model (HEC-HMS) was used to compute Chinook River and tributary inflows for use as input to the hydrodynamic model at the project area boundary. The hydrodynamic model (RMA-10) was used to generate information on water levels, velocities, salinity, and inundation during both normal tides and 100-year storm conditions under existing conditions and under the restoration alternatives. The RMA-10 model was extended well upstream of the normal tidal flats into the watershed domain to correctly simulate flooding and drainage with tidal effects included, using the wetting and drying schemes. The major conclusion of the hydrologic and hydrodynamic modeling study was that restoration of the tidal functions in the Chinook River estuary would be feasible through opening or removal of the tide gate. Implementation of the preferred alternative (removal of the tide gate, restoration of the channel under Hwy 101 to a 200-foot width, and construction of an internal levee inside the project area) would provide the required restorations benefits (inundation, habitat, velocities, and salinity penetration, etc.) and meet flood protection requirements. The alternative design included design of storage such that relatively little difference in the drainage or inundation upstream of Chinook River Valley Road would occur as a result of the proposed restoration activities.

Khangaonkar, Tarang P.; Breithaupt, Stephen A.; Kristanovich, Felix C.

2006-08-03

9

Interoceanic Canal Studies - 1970. Annex V. Study of Engineering Feasibility.  

National Technical Information Service (NTIS)

The Study of Engineering Feasibility was made pursuant to a request by the Atlantic-Pacific Interoceanic Canal Study Commission that the Chief of Engineers determine the engineering feasibility of constructing a sea-level canal between the Atlantic and Pa...

1970-01-01

10

Stirling engine design and feasibility for automotive use  

Microsoft Academic Search

The book is based on two reports dealing with theoretical considerations in the design of Stirling engines for automotive use, and with a feasibility study for an 80-100-hp automotive Stirling engine. The basic principles of heat engines are explained, and the Stirling engine is introduced, with attention given to the variety of Stirling engine types and their utility in comparison

Collie

1979-01-01

11

The Feasibility of Oil Analysis for Air Force Diesel Engines.  

National Technical Information Service (NTIS)

A feasibility study dealing with the implementation of an oil analysis program for Air Force diesel engines is described. Engine types were categorized and information assembled on characteristics, rebuild costs, and rebuild rates. Promising equipment cla...

J. P. Cuellar L. L. Stavinoha J. D. Tosh J. A. Russell B. R. Wright

1979-01-01

12

On the Feasibility of Situational Method Engineering  

Microsoft Academic Search

Given the plethora of methods for information systems development and the fact that no one method is equally suitable for every type of application domain, various proposals have been made to allow for the adaption (tailoring) of methods to better suit the needs of a specific application domain. Among these proposals is the idea of method engineering, which can be

Arthur H. M. Ter Hofstede; T. F. Verhoef

1997-01-01

13

Feasibility study of a contained pulsed nuclear propulsion engine  

NASA Astrophysics Data System (ADS)

The result of a feasibility analysis of a contained pulsed nuclear propulsion (CPNP) engine concept utilizing the enormously dense energy generated by small nuclear detonations is presented in this article. This concept was initially proposed and studied in the 1950s and 1960s under the program name HELIOS. The current feasibility of the concept is based upon materials technology that has advanced to a state that allows the design of pressure vessels required to contain the blast associated with small nuclear detonations. The impulsive nature of the energy source provides the means for circumventing the materials thermal barriers that are inherent in steady-state nuclear propulsion concepts. The rapid energy transfer to the propellant results in high thrust levels for times less than 1 s following the detonation. The preliminary feasibility analysis using off-the-shelf materials technology appears to indicate that the CPNP concept can have thrust-to-weight ratios on the order of 1 or greater. Though the specific impulse is not a good indicator for impulsive engines, an operating-cycle averaged specific impulse of approximately 1000 or greater seconds was calculated.

Parlos, Alexander G.; Metzger, John D.

1994-03-01

14

Engineering feasibility of in-situ subsurface isolation barriers  

Microsoft Academic Search

In the remediation of radioactive waste disposal sites there are occasional situations where it is not feasible to remove the waste or contaminated soil and a containment approach is more appropriate. This paper is a discussion of a DOE funded research and development study [1] on the feasibility of in situ construction bottom barrier containment structures in soil under and

2007-01-01

15

Feasibility of Magnetic Bearings for Advanced Gas Turbine Engines.  

National Technical Information Service (NTIS)

The application of active magnetic bearings to advanced gas turbine engines will provide a product with major improvements compared to current oil lubricated bearing designs. A rethinking of the engine rotating and static structure design is necessary and...

D. Hibner L. Rosado

1992-01-01

16

Energy system feasibility study of an Otto cycle\\/Stirling cycle hybrid automotive engine  

Microsoft Academic Search

The aim of this study was to investigate the feasibility of utilising a Stirling cycle engine as an exhaust gas waste heat recovery device for an Otto cycle internal combustion engine (ICE) in the context of an automotive power plant. The hybrid arrangement would produce increased brake power output for a given fuel consumption rate when compared to an ICE

Barry Cullen; Jim McGovern

2010-01-01

17

Session 6: Magma Energy: Engineering Feasibility of Energy Extraction from Magma Bodies  

SciTech Connect

Extensive quantities of high-quality energy are estimated to be available from molten magma bodies existing within 10 Km of the US continent's surface. A five-year study sponsored by DOE/BES demonstrated that extraction of energy from these melts was scientifically feasible. The next stage of assessment is to evaluate the engineering feasibility of energy extraction and provide a preliminary economic evaluation. Should the second step demonstrate engineering feasibility, the third step would include detailed economic, market and commercialization endeavors. Evaluation of the engineering feasibility will be initiated in FY 84 in a program supported by DOE/GHTD and managed by Dave Allen. The project will be managed by Sandia Labs in James Kelsey's Geothermal Technology Development Division. The project will continue to draw on expertise throughout the country, especially the scientific base established in the previous BES Magma Energy Program.

Traeger, R.K.

1983-12-01

18

Feasibility study of the wave disk micro-engine operation  

NASA Astrophysics Data System (ADS)

The development of micro turbine engines has been strongly intensified in recent years. Since turbo-component efficiency has become very low due to the downsizing effect, the micro wave rotor is expected to be applied for the improvement of the performance of ultra-micro gas turbines, increasing the cycle pressure ratio. But wave rotors can also be used in another configuration. Here replacement of steady flow engine components by unsteady flow devices is proposed and analyzed. Applying a combustion chamber only and using oblique blades to form the rotor cells, net power can be taken from the rotor. In that way the use of an inefficient, micro-scale turbo unit can be omitted. Conventional construction of unsteady devices in the form of a wave rotor cannot be realized in MEMS technology. The new idea of a wave disk gives the possibility of an easy implementation of a wave engine in MEMS technology. In the proposed solution the wave disk plays the role of an active compression-decompression unit and torque generator. Appropriate port geometry with straight or oblique blades forming the disk channels generates torque. The engine disk rotates with a speed much lower than the conventional turbo unit and simplifies the bearing problem. Also the construction of an electric generator could be simpler. This paper presents the proposed flow schemes, thermodynamic cycle, exemplary engine construction and some preliminary results of simulation of the MEMS wave engine utilizing the wave disk geometry.

Piechna, Janusz R.

2006-09-01

19

Krypton-85 hydrofracture engineering feasibility and safety evaluation  

SciTech Connect

Engineering studies have been made to determine the hazards associated with the disposal of /sup 85/Kr using the hydrofracture process. To assess the hazards, an effort has been made to identify the equipment required to entrain and dissolve the noble gas into the grout stream at hydrofracture pressure (up to 350 bar). Off-the-shelf or slightly modified equipment has been identified for safe and effective compression and gas-grout mixing. Each monthly injection disposes of 1.6 x 10/sup 6/ Ci of /sup 85/Kr. By connecting only one gas cylinder to the injection system at a time, the maximum amount of krypton likely to be released as a result of equipment failure is limited to 128,000 Ci. An evaluation by Los Alamos Technical Associates shows that releasing this amount of gas in less than one hour under worst-case meteorological conditions through a 30-m stack would result in a whole-body dose of 170 millirem at a distance of 1 km from the facility. A krypton collection and recovery system can further reduce this dose to 17 millirem; increasing the distance to the site boundary to 3 km can also reduce the dose by a factor of ten. Lung and skin dose estimates are 1.6 and 120 times the whole-body dose, respectively. These are all worst-case values; releases under more typical conditions would result in a significantly lower dose. No insurmountable safety or engineering problems have been identified.

Peretz, F.J.; Muller, M.E.; Pan, P.Y.

1981-07-01

20

Energy efficiency and economic feasibility of CCHP driven by stirling engine  

Microsoft Academic Search

This paper deals with the problem of energy efficiency evaluation and economic feasibility analysis of a small scale trigeneration system for combined cooling, heating and power generation (CCHP) with an available Stirling engine. Trigeneration systems have a large potential of energy saving and economical efficiency. The decisive values for energetic efficiency evaluation of such systems are the primary energy rate

X. Q. Kong; R. Z. Wang; X. H. Huang

2004-01-01

21

Testing Engine Generator Sets with the Programmable Diagnostic System Model 770 (PDS-770) - A Feasibility Study.  

National Technical Information Service (NTIS)

This report presents findings of a study to determine the feasibility of using the Model 770 Programmable Diagnostic System (PDS-770) to test 1.5, 10, and 45 KW Engine Generator Sets. The PDS-770 is capable of diagnosing malfunctions in spark and compress...

1970-01-01

22

Exploring Estuaries  

NSDL National Science Digital Library

Exploring Estuaries introduces students of various ages to the ecology of estuaries, places where freshwater rivers and streams flow into the ocean, mixing with the seawater. It is part of a broader effort by the National Estuary Program to educate the general public about estuaries and to restore and protect these sensitive ecosystems. It offers interactive games and activities as well as virtual tours of Long Island Sound and the Barataria-Terrebonne Estuarine Complex near New Orleans. A glossary page defines technical terms used throughout the site. Resources also are provided for teachers and students interested in learning more about related organizations, publications, and websites.

23

Assessment of the need for and feasibility of establishing a national reactor engineering simulator facility  

SciTech Connect

A study was conducted by the Department of Energy's Office of Nuclear Power Systems to determine the need for and feasibility of establishing a reactor engineering simulator facility at a National Laboratory. Input was obtained from a wide cross section of the Nation's nuclear industry, the Department's National Laboratories, the Nuclear Regulatory Commission (NRC), and the Advisory Committee on Reactor Safeguards in carrying out this study. Based on this input, the Department concludes that the proposed facility would not significantly contribute to the capability of the Nation's nuclear industry or the Department to foster research in generic design improvements and simplifications. Furthermore, the Department concludes that such a facility, although it is theoretically feasible, is not practical from an engineering viewpoint, and the significant national effort and expense, which would be required to develop, construct, and operate such a facility, is not justified.

Not Available

1981-12-01

24

Engineering and Economic Feasibility of Using Poultry Litter as a Fuel to Generate Electric Power at Maryland's Eastern Correctional Institute.  

National Technical Information Service (NTIS)

This report presents an analysis of the engineering, environmental, and economic feasibility of the Eastern Correctional Institute (ECI) meeting its electric power and thermal requirements by relying on poultry litter as a fuel. In addition to satisfying ...

S. L. Estomin G. Walters A. Prasad J. Ross

1998-01-01

25

Geothermal resource, engineering and economic feasibility study for the City of Ouray, Colorado. Final report  

SciTech Connect

A geothermal energy feasibility study has been performed for the City of Ouray, Colorado, to determine the potential economic development opportunities to the City. The resource assessment indicates the resource to be associated with the Ouray fault zone, the Leadville limestone formation, the high thermal gradient in the area of the San Juan mountains, and the recharge from precipitation in the adjacent mountains. Four engineering designs of alternative sizes, costs, applications, and years of start-up have been defined to offer the City a range of development scales. Life cycle cost analyses have been conducted for cases of both public and private ownership. All systems are found to be feasible on both economic and technical grounds. 49 refs., 8 figs.

Meyer, R.T.; Raskin, R.; Zocholl, J.R.

1982-07-31

26

The electrochemical reduction of carbon dioxide to formate/formic acid: engineering and economic feasibility.  

PubMed

The engineering and economic feasibility of large-scale electrochemical reduction of carbon dioxide to formate salts and formic acid is the focus of this Full Paper. In our study we investigated the long-term performance of tin and other proprietary catalysts in the reduction of carbon dioxide to formate/formic acid at a gas/solid/liquid interface, using a flow-through reactor. The overall economics and energy consumption of the process are evaluated through a value chain analysis. The sensitivity of the net present value of the process to various process parameters is examined. PMID:21922681

Agarwal, Arun S; Zhai, Yumei; Hill, Davion; Sridhar, Narasi

2011-09-19

27

Modeling the Feasibility of Using Fuel Cells and Hydrogen Internal Combustion Engines in Remote Renewable Energy Systems: Preprint  

Microsoft Academic Search

Recent advances in hydrogen fuel cell and internal combustion engine technologies have enabled new energy options for supplying electrical power in remote, off-grid areas. The objective of this investigation is to determine under which conditions wind turbines and PV systems can feasibly power electrolyzers to generate and store hydrogen for remote power generation using fuel cells and internal combustion engines.

J. Cotrell; W. Pratt

2003-01-01

28

Feasibility analysis of an open cycle thermoacoustic engine with internal pulse combustion  

NASA Astrophysics Data System (ADS)

Thermoacoustic engines convert thermal energy into acoustic energy with few or no moving parts, thus they require little maintenance, are highly reliable, and are inexpensive to produce. These traits make them attractive for applications in remote or portable power generation, where a linear alternator converts the acoustic power into electric power. Their primary application, however, is in driving thermoacoustic refrigerators, which use acoustic power to provide cooling at potentially cryogenic temperatures, also without moving parts. This dissertation examines the feasibility of a new type of thermoacoustic engine, where mean flow and an internal pulse combustion process replace the hot heat exchanger in a traditional closed cycle thermoacoustic engine, thereby eliminating the heat exchanger's cost, inefficiency, and thermal expansion stresses. The theory developed in this work reveals that a large temperature difference must exist between the hot face of the regenerator and the hot combustion products flowing into it, and that much of the convective thermal energy input from the combustion process is converted into conductive and thermoacoustic losses in the regenerator. The development of the Thermoacoustic Pulse Combustion Engine, as described in this study, is designed to recover most of this lost thermal energy by routing the inlet pipes through the regenerator to preheat the combustion reactants. Further, the developed theory shows that the pulse combustion process has the potential to add up to 7% to the engine's acoustic power output for an acoustic pressure ratio of 10%, with linearly increasing contributions for increasing acoustic pressure ratios. Computational modeling and optimization of the Thermoacoustic Pulse Combustion Engine yield thermal efficiencies of about 20% for atmospheric mean operating pressures, though higher mean engine pressures increase this efficiency considerably by increasing the acoustic power density relative to the thermal losses. However, permissible mean engine pressures are limited by the need to avoid fouling the regenerator with condensation of water vapor out of the cold combustion products. Despite lower acoustic power densities, the Thermoacoustic Pulse Combustion Engine is shown to be well suited to portable refrigeration and power generation applications, due to its reasonable efficiency and inherent simplicity and compactness.

Weiland, Nathan T.

29

Exploring Estuaries  

NSDL National Science Digital Library

This site offers several ways to explore the importance of estuaries. Virtual tours of the Barataria-Terrebone Estuarine Complex and the Long Island Sound offer photos and text of each area explain their importance to humans, wildlife, and larger ecosystems. Additional resources for kids and adults are linked. A glossary page offers a list of vocabulary associated with estuaries. The site also offers a games and activities section for kids that has coloring sheets for young children, and inquiry-based interactive games for older kids. The games include a "Who Am I" animal identification game, and a game called "Solve a Mystery" where players must follow and investigation into what's wrong with an estuary, and make a decision on the cause of the problem. There are several possible mysteries to solve, each with a different solution.

30

GEEF: a geothermal engineering and economic feasibility model. Description and user's manual  

SciTech Connect

The model is designed to enable decision makers to compare the economics of geothermal projects with the economics of alternative energy systems at an early stage in the decision process. The geothermal engineering and economic feasibility computer model (GEEF) is written in FORTRAN IV language and can be run on a mainframe or a mini-computer system. An abbreviated version of the model is being developed for usage in conjunction with a programmable desk calculator. The GEEF model has two main segments, namely (i) the engineering design/cost segment and (ii) the economic analysis segment. In the engineering segment, the model determines the numbers of production and injection wells, heat exchanger design, operating parameters for the system, requirement of supplementary system (to augment the working fluid temperature if the resource temperature is not sufficiently high), and the fluid flow rates. The model can handle single stage systems as well as two stage cascaded systems in which the second stage may involve a space heating application after a process heat application in the first stage.

Not Available

1982-09-01

31

Tidal Study of Three Oregon Estuaries.  

National Technical Information Service (NTIS)

During the summer of 1969 the Civil Engineering Department at Oregon State University measured tidal elevations and current velocities in the Yaquina, Alsea, and Siletz estuaries. Data were gathered on the physical characteristics (depths, areas, volumes,...

C. R. Goodwin E. W. Emmett B. Glenne

1970-01-01

32

Classification of Estuaries  

NSDL National Science Digital Library

This text states that although all estuaries are similar in that they are semi-enclosed bodies of brackish water, they are categorized with regard to geological characteristics, and further distinguished on the basis of stratification and circulation patterns. According to their geological characteristics, estuaries are classified as: drowned river valleys or coastal-plain estuaries, bar-built estuaries or lagoons, fjord-type estuaries, and tectonically caused estuaries. Each type is explained in detail and examples are given for each.

33

Classification of Estuaries  

NSDL National Science Digital Library

This text states that although all estuaries are similar in that they are semi-enclosed bodies of brackish water, they are categorized with regard to geological characteristics, and further distinguished on the basis of stratification and circulation patterns. According to their geological characteristics, estuaries are classified as: drowned river valleys or coastal-plain estuaries, bar-built estuaries or lagoons, fjord-type estuaries, and tectonically caused estuaries. Each type is explained in detail and examples are given for each.

Oberrecht, Kenn

2007-01-30

34

Wave Motion in an Estuary.  

National Technical Information Service (NTIS)

Wave climate in an estuary with a strongly changing topography was investigated. Wave effects on coastal engineering works, on morphology and on the vertical movements of large ships by long-period waves were measured by wave-rider buoys and wave gages. D...

V. Barthel

1982-01-01

35

A feasibility study on using inkjet technology, micropumps, and MEMs as fuel injectors for bipropellant rocket engines  

NASA Astrophysics Data System (ADS)

Control over drop size distributions, injection rates, and geometrical distribution of fuel and oxidizer sprays in bi-propellant rocket engines has the potential to produce more efficient, more stable, less polluting rocket engines. This control also offers the potential of an engine that can be throttled, working efficiently over a wide range of output thrusts. Inkjet printing technologies, MEMS fuel atomizers, and piezoelectric injectors similar in concept to those used in diesel engines are considered for their potential to yield a new, more active injection scheme for a rocket engine. Inkjets are found to be unable to pump at sufficient pressures, and have possibly dangerous failure modes. Active injection is found to be feasible if high pressure drop along the injector plate is used. A conceptual design is presented and its basic behavior assessed.

Glynne-Jones, Peter; Coletti, M.; White, N. M.; Gabriel, S. B.; Bramanti, C.

2010-07-01

36

Estuaries: Finding the Balance  

NSDL National Science Digital Library

Students can use this resource from the National Geographic to examine the conflict between development and the environment by focusing on estuaries across the United States. Its objectives are for students to learn about the environmental and economic importance of estuaries, consider the conflicts that arise because of the many uses of estuaries, research a specific estuary and the problems and solutions that have developed around it, and suggest compromises that might be made in order to protect both estuaries and economic development. To meet these objectives, students are directed to review a number of websites about estuaries and then to answer questions concerning environmental issues (e.g., What are the specific ecological characteristics of estuaries? What are some of the signs that an estuary is in trouble as a habitat?) and economic issues (e.g., How might proximity to major cities impact estuaries? To what degree should economic activity dictate the outcome of estuaries?).

Xpeditions NatGeo (National Geographic Society;)

2008-04-30

37

National Estuaries Day  

NSDL National Science Digital Library

Get the most out of National Estuaries Day (October 5, 2002) by visiting this Web site from the National Oceanic and Atmospheric Administration (NOAA). Follow a link to Estuary Live!, which offers online interactive fieldtrips through a number of estuaries around the nation. Guided tours of eight estuaries will be webcast live October 3 and 4, supplemented by videos from a number of other estuaries. Internet participants "will have an opportunity to see the fascinating creatures that make estuaries their home and experience the diversity of estuarine ecosystems." Viewers may submit questions during the webcasts or videos, which will be answered by tour guides and educators from the featured estuaries. Click on About Estuaries for an introduction to estuarine ecosystems and for links to a number of Web sites that "provide general information, curriculums and helpful references on estuaries."

2002-01-01

38

Feasibility and emissions of compression ignition engines fueled with waste vegetable oil  

Microsoft Academic Search

Research and experience has shown that vegetable oil can be processed, by transesterification, into a useable fuel for compression ignition engines. Earlier research examined using straight vegetable oil as a fuel, but found it to cause detrimental engine problems. Trial and error has shown that heating the vegetable oil prior to injection, is a viable option. A diesel vehicle engine

Morgan H Crawford

2003-01-01

39

Feasibility of dual-fuel engine block concept in large cogeneration plants  

SciTech Connect

Fairbanks Morse Engine Division of Coltec Industries is ready to move into the cogeneration market with its well established engine program. Over the past six years the company has been refining and improving both the 38D8-1/8 opposed piston and PC2.5 dual-fuel engines in several areas. The most important targets achieved are higher power output, lower exhaust emissions, better fuel economy, better maintainability and longer life. The result is the Enviro-Design series of engines which the company believes will find broad application in the power generation and cogeneration fields. 3 figs.

Not Available

1993-06-01

40

Application of a three-dimensional water quality model to the James Estuary. Master's thesis  

SciTech Connect

Water quality models continue to increase in options and accuracy as super computer access becomes a reality for water quality management. The US Army Corps of Engineers (USACE) Waterways Experiment Station (WES), in Vicksburg, Mississippi has developed a state of the art modeling framework for simulating the hydrodynamics and water quality standards of the Chesapeake Bay. As environmental engineers focus more attention on Bays tributaries this year, this complicated model must be accurately applied to the major freshwater rivers emptying into the Bay. To discover the feasibility of applying the models to a smaller estuary system, the Chesapeake Bay model was reconfigured and applied to the James River Estuary in Virginia. The alteration mandated input file data reconstruction and development, basin mapping, and site specific code adjustments for the models and the postprocessor. The model size and memory needs dictate super computer enrollment for accurate and timely system utilization. The model was calibrated using salinity data on the James Estuary, and verified by dissolved oxygen and chlorophyll a responses to nutrient loadings. A model sensitivity analysis of the results was conducted to ensure that reliable results were obtained.

Larsen, C.J.

1993-05-01

41

80-100 HP Stirling engine feasibility study. Progress report No. 15, July--September 1976  

Microsoft Academic Search

Ford Motor Company has sponsored research and development of a 170-hp swashplate-type of Stirling engine suitable for application to a passenger car having a curb weight in the neighborhood of 4600 lb. The success of this application program has justified the need for investigating the application of the Stirling engine to passenger vehicles of smaller size and lighter weight. Progress

Postma

1976-01-01

42

80- to 100-hp Stirling engine feasibility study. Progress report No. 21, January--March 1977  

Microsoft Academic Search

Ford Motor Company has sponsored research and development of a 170 hp swashplate-type of Stirling engine suitable for application to a passenger car having a curb weight in the neighborhood of 4,600 pounds. The success of this program has justified the need for investigating the application of the Stirling engine to passenger vehicles of smaller size and lighter weight. Progress

Postma

1977-01-01

43

rRNA (rrn) Operon-Engineered Bacillus subtilis as a Feasible Test Organism for Antibiotic Discovery  

PubMed Central

Bacillus subtilis contains 10 rRNA (rrn) operons. We found that rRNA operon-engineered B. subtilis strain RIK543, with only the rrnO operon, is specifically hypersensitive to RNA polymerase inhibitors such as rifamycin SV and rifampin (80-fold and 20-fold, respectively). In pilot screening experiments, we found actinomycete isolates successfully at an incidence of 1.9% (18/945) that produced antibacterials that were detectable only with RIK543 as the test organism. Strain RIK543 may be a feasible test organism for the discovery of novel RNA polymerase inhibitors.

Tanaka, Yukinori; Nanamiya, Hideaki; Yano, Koichi; Kakugawa, Koji; Kawamura, Fujio

2013-01-01

44

Compton interaction tomography; I. Feasibility studies for applications in earthquake engineering  

SciTech Connect

Feasibility of applying Compton Interaction Tomographic (CIT) processes for nondestructive testing of massive extended systems is studied on a laboratory prototype device. The principles of Compton interaction between electromagnetic radiation and matter underly the technique. Experimental studies are conducted to detect features such as iron rebars and air voids contained in a concrete medium. Computer simulation studies have been made to supplement experimental results.

Gautam, S.R.; Hopkins, F.F.; Klinksiek, R.; Morgan, I.L.

1983-04-01

45

Evaluation of Technical Feasibility of Homogeneous Charge Compression Ignition (HCCI) Engine Fueled with Hydrogen, Natural Gas, and DME  

SciTech Connect

The objective of the proposed project was to confirm the feasibility of using blends of hydrogen and natural gas to improve the performance, efficiency, controllability and emissions of a homogeneous charge compression ignition (HCCI) engine. The project team utilized both engine simulation and laboratory testing to evaluate and optimize how blends of hydrogen and natural gas fuel might improve control of HCCI combustion. GTI utilized a state-of-the art single-cylinder engine test platform for the experimental work in the project. The testing was designed to evaluate the feasibility of extending the limits of HCCI engine performance (i.e., stable combustion, high efficiency and low emissions) on natural gas by using blends of natural gas and hydrogen. Early in the project Ricardo provided technical support to GTI as we applied their engine performance simulation program, WAVE, to our HCCI research engine. Modeling support was later provided by Digital Engines, LLC to use their proprietary model to predict peak pressures and temperatures for varying operating parameters included in the Design of Experiments test plan. Digital Engines also provided testing support for the hydrogen and natural gas blends. Prof. David Foster of University of Wisconsin-Madison participated early in the project by providing technical guidance on HCCI engine test plans and modeling requirements. The main purpose of the testing was to quantify the effects of hydrogen addition to natural gas HCCI. Directly comparing straight natural gas with the hydrogen enhanced test points is difficult due to the complexity of HCCI combustion. With the same air flow rate and lambda, the hydrogen enriched fuel mass flow rate is lower than the straight natural gas mass flow rate. However, the energy flow rate is higher for the hydrogen enriched fuel due to hydrogen's significantly greater lower heating value, 120 mJ/kg for hydrogen compared to 45 mJ/kg for natural gas. With these caveats in mind, an analysis of test results indicates that hydrogen enhanced natural gas HCCI (versus neat natural gas HCCI at comparable stoichiometry) had the following characteristics: (1) Substantially lower intake temperature needed for stable HCCI combustion; (2) Inconclusive impact on engine BMEP and power produced; (3) Small reduction in the thermal efficiency of the engine; (4) Moderate reduction in the unburned hydrocarbons in the exhaust; (5) Slight increase in NOx emissions in the exhaust; (6) Slight reduction in CO2 in the exhaust; and (7) Increased knocking at rich stoichiometry. The major accomplishments and findings from the project can be summarized as follows: (1) A model was calibrated for accurately predicting heat release rate and peak pressures for HCCI combustion when operating on hydrogen and natural gas blends. (2) A single cylinder research engine was thoroughly mapped to compare performance and emissions for micro-pilot natural gas compression ignition, and HCCI combustion for neat natural gas versus blends of natural gas and hydrogen. (3) The benefits of using hydrogen to extend, up to a limit, the stable operating window for HCCI combustion of natural gas at higher intake pressures, leaner air to fuel ratios or lower inlet temperatures was documented.

John Pratapas; Daniel Mather; Anton Kozlovsky

2007-03-31

46

Feasibility of Reduced Chemical Kinetic Mechanisms of Methane in Internal Combustion Engine Simulations  

NASA Astrophysics Data System (ADS)

Three reduced chemical kinetic mechanisms of methane combustion were tested and compared with the standard detailed scheme GriMech 3.0., using the internal combustion engine (ICE) model of Chemkin 4.02 [1]. This study shows acceptable concordances in the prediction of temperature and main species profiles. But reduced schemes were incapables to predict all polluant emissions in an internal combustion engine.

Ennetta, Ridha; Said, Rachid

2008-09-01

47

Engineering feasibility analysis for in-situ stabilization of Canonsburg residues. [UMTRA project  

SciTech Connect

The US Department of Energy is considering several methods for carrying out remedial actions in Canonsburg, Pennsylvania, at the site of an inactive uranium-processing mill. The main objective of this study is to determine the feasibility of in-situ stabilization as the remedial action. In-situ stabilization is an alternative to site decontamination and offsite disposal. The problems associated with offsite hauling of large quantities of contaminated material and with the location and development of a new disposal site could be avoided by the implementation of an in-situ stabilization concept. In addition, the in-situ approach would be more cost-effective than offsite disposal. This study will establish that a technically feasible and implementable in-situ stabilization concept can be developed that meets regulatory requirements and is cost effective. This study in no way commits the DOE to implement any specific actions described herein. 11 refs., 30 figs., 24 tabs.

Not Available

1982-01-01

48

80- to 100-HP Stirling Engine Feasibility Study. Progress Report No. 21, January--March 1977.  

National Technical Information Service (NTIS)

Ford Motor Company has sponsored research and development of a 170 hp swashplate-type of Stirling engine suitable for application to a passenger car having a curb weight in the neighborhood of 4,600 pounds. The success of this program has justified the ne...

N. D. Postma

1977-01-01

49

80-100 HP Stirling Engine Feasibility Study. Progress Report No. 15, July--September 1976.  

National Technical Information Service (NTIS)

Ford Motor Company has sponsored research and development of a 170-hp swashplate-type of Stirling engine suitable for application to a passenger car having a curb weight in the neighborhood of 4600 lb. The success of this application program has justified...

N. D. Postma

1976-01-01

50

Great Lakes estuaries  

Microsoft Academic Search

Conclusions  According to the geomorphology and physiography classification scheme for estuaries proposed by Pritchard (1967) and presented\\u000a in Kennish (1986), Great Lakes estuaries can be classified as Type A: drowned river valleys or rias. The termination of Wisconsinian\\u000a glaciation, which resulted in a eustatic rise in sea level of somewhat over 100 m and the formation of such Atlantic coast\\u000a estuaries

Charles E. Herdendorf

1990-01-01

51

Learning Lessons from Estuaries  

ERIC Educational Resources Information Center

|There is something that draws all people to the sea and especially to the fertile estuaries that nuzzle up to its shores. An estuary serves as both a nursery and a grave for sea creatures. If life evolved from some primordial sea, it may well have been an estuary--a place where ocean and rivers meet and fresh and salty waters mingle in the…

Schnittka, Christine

2006-01-01

52

DYNAMIC ESTUARY MODEL PERFORMANCE  

EPA Science Inventory

Applications of the Dynamic Estuary Model (DEM) to both the Delaware and Potomac Estuaries by the Environmental Protection Agency during the 1970s are summarized and evaluated. Methods for calibrating, refining, and validating this model, and statistics for evaluating its perform...

53

Genome Engineering in Vibrio cholerae: A Feasible Approach to Address Biological Issues  

PubMed Central

Although bacteria with multipartite genomes are prevalent, our knowledge of the mechanisms maintaining their genome is very limited, and much remains to be learned about the structural and functional interrelationships of multiple chromosomes. Owing to its bi-chromosomal genome architecture and its importance in public health, Vibrio cholerae, the causative agent of cholera, has become a preferred model to study bacteria with multipartite genomes. However, most in vivo studies in V. cholerae have been hampered by its genome architecture, as it is difficult to give phenotypes to a specific chromosome. This difficulty was surmounted using a unique and powerful strategy based on massive rearrangement of prokaryotic genomes. We developed a site-specific recombination-based engineering tool, which allows targeted, oriented, and reciprocal DNA exchanges. Using this genetic tool, we obtained a panel of V. cholerae mutants with various genome configurations: one with a single chromosome, one with two chromosomes of equal size, and one with both chromosomes controlled by identical origins. We used these synthetic strains to address several biological questions—the specific case of the essentiality of Dam methylation in V. cholerae and the general question concerning bacteria carrying circular chromosomes—by looking at the effect of chromosome size on topological issues. In this article, we show that Dam, RctB, and ParA2/ParB2 are strictly essential for chrII origin maintenance, and we formally demonstrate that the formation of chromosome dimers increases exponentially with chromosome size.

Val, Marie-Eve; Skovgaard, Ole; Ducos-Galand, Magaly; Bland, Michael J.; Mazel, Didier

2012-01-01

54

Multi-lingual Search Engine to Access PubMed Monolingual Subsets: A Feasibility Study.  

PubMed

PubMed contains many articles in languages other than English but it is difficult to find them using the English version of the Medical Subject Headings (MeSH) Thesaurus. The aim of this work is to propose a tool allowing access to a PubMed subset in one language, and to evaluate its performance. Translations of MeSH were enriched and gathered in the information system. PubMed subsets in main European languages were also added in our database, using a dedicated parser. The CISMeF generic semantic search engine was evaluated on the response time for simple queries. MeSH descriptors are currently available in 11 languages in the information system. All the 654,000 PubMed citations in French were integrated into CISMeF database. None of the response times exceed the threshold defined for usability (2 seconds). It is now possible to freely access biomedical literature in French using a tool in French; health professionals and lay people with a low English language may find it useful. It will be expended to several European languages: German, Spanish, Norwegian and Portuguese. PMID:23920740

Darmoni, Stéfan J; Soualmia, Lina F; Griffon, Nicolas; Grosjean, Julien; Kerdelhué, Gaétan; Kergourlay, Ivan; Dahamna, Badisse

2013-01-01

55

Engineering and economic feasibility of using poultry litter as a fuel to generate electric power at Maryland`s Eastern Correctional Institute  

Microsoft Academic Search

This report presents an analysis of the engineering, environmental, and economic feasibility of the Eastern Correctional Institute (ECI) meeting its electric power and thermal requirements by relying on poultry litter as a fuel. In addition to satisfying all or a portion of the utility requirements of ECI, a maximum\\/medium security prison located in Princess Anne, Maryland, the use of poultry

S. L. Estomin; G. Walters; A. Prasad; J. Ross

1998-01-01

56

Brunswick Estuary Study.  

National Technical Information Service (NTIS)

Intensive surveys of the Brunswick and Medway Estuaries were conducted from August 4 through August 6, 1976 by the Environmental Protection Division of the Georgia Department of Natural Resources. The purpose of the surveys was to determine present dissol...

1976-01-01

57

Volunteer Estuary Monitoring  

NSDL National Science Digital Library

This online method manual from EPA describes how to conduct estuary monitoring programs, with step-by-step guides for chemical, physical and biological sampling and data interpretation. Also describes how to plan and maintain a volunteer force, with tips on liability and financial issues, volunteer recruiting training and retention. Addresses quality assurance so that results have weight. Provides an overview of estuarine science, threats to estuaries and some solutions.

58

Characteristics of Danish estuaries  

Microsoft Academic Search

We review various aspects of the structure and functioning of Danish estuaries from data collected by the National Monitoring\\u000a Program and from information in published sources. We present data on the physical, chemical, and biological characteristics\\u000a of estuaries in Denmark, we evaluate the functioning of these systems as filters and transformers of nutrients and we evaluate\\u000a the outlook for Danish

Daniel J. Conley; Hanne Kaas; Flemming Møhlenberg; Bjarke Rasmussen; Jørgen Windolf; Flemming Mohlenberg; Jorgen Windolf

2000-01-01

59

Feasibility of an Ion Engine for Engineering Test Satellite. 3: Examination of Electronic Instruments Mounted on the Satellite 3 for the Purpose of Technical Study.  

National Technical Information Service (NTIS)

Design constraints and characteristics are described of a Japanese (mercury) ion engine for spacecraft attitute control. Specifications for engine tests are given: starting sequence, data transmission, checkout. The ETS-III satellite mission for engine ch...

I. Kudo

1975-01-01

60

DELAWARE ESTUARY PCB MODEL  

EPA Science Inventory

The Delaware River Basin Commission recently completed the first phase of a program to develop and implement Total Maximum Daily Loads (TMDLs) for toxic pollutants for the Delaware Estuary. This complex body of water extends from the head of tide at Trenton, NJ (River Mile 133.2...

61

Feasibility study on oil droplet flow investigations inside aero engine bearing chambers -- PDPA techniques in combination with numerical approaches  

Microsoft Academic Search

The present paper deals with oil droplet flow phenomena in aero engine bearing chambers. An experimental investigation of droplet sizes and velocities utilizing a Phase Doppler Particle Analyzer (PDPA) has been performed for the first time in bearing chamber atmospheres under real engine conditions. Influences of high rotational speeds are discussed for individual droplet size classes. Although this is an

A. Glahn; M. Kurreck; M. Willmann; S. Wittig

1996-01-01

62

80-100 HP Stirling Engine Feasibility Study. Progress Report No. 18, for the Quarter October--December 1976.  

National Technical Information Service (NTIS)

Progress is reported for a program to investigate the use of an 80 to 100 hp Stirling engine in a 2500 to 3000 lb. passenger car. The engine was installed in a dynamometer test cell, and dynamometer emissions of HC, CO, and NO/sub x/ were measured. Fuel e...

N. D. Postma

1976-01-01

63

Engineering and economic feasibility of using poultry litter as a fuel to generate electric power at Maryland`s Eastern Correctional Institute  

SciTech Connect

This report presents an analysis of the engineering, environmental, and economic feasibility of the Eastern Correctional Institute (ECI) meeting its electric power and thermal requirements by relying on poultry litter as a fuel. In addition to satisfying all or a portion of the utility requirements of ECI, a maximum/medium security prison located in Princess Anne, Maryland, the use of poultry litter as a fuel would reduce the amount of poultry waste currently used on the Eastern Shore as fertilizer. Based on the engineering and environmental assessments conducted, three alternative scenarios to satisfy ECI`s electric power supply and thermal requirements using poutlry litter as a fuel were developed. For all scenarios, as well as a base case defined by current operations at ECI, 20-year life-cycle costs were estimated based on projections of usage, capital costs, fuel costs, labor costs, and other relevant factors.

Estomin, S.L.; Walters, G.; Prasad, A.; Ross, J.

1998-02-16

64

Visualizing feasible operating ranges within tissue engineering systems using a "windows of operation" approach: a perfusion-scaffold bioreactor case study.  

PubMed

Tissue engineering approaches to developing functional substitutes are often highly complex, multivariate systems where many aspects of the biomaterials, bio-regulatory factors or cell sources may be controlled in an effort to enhance tissue formation. Furthermore, success is based on multiple performance criteria reflecting both the quantity and quality of the tissue produced. Managing the trade-offs between different performance criteria is a challenge. A "windows of operation" tool that graphically represents feasible operating spaces to achieve user-defined levels of performance has previously been described by researchers in the bio-processing industry. This paper demonstrates the value of "windows of operation" to the tissue engineering field using a perfusion-scaffold bioreactor system as a case study. In our laboratory, perfusion bioreactor systems are utilized in the context of bone tissue engineering to enhance the osteogenic differentiation of cell-seeded scaffolds. A key challenge of such perfusion bioreactor systems is to maximize the induction of osteogenesis but minimize cell detachment from the scaffold. Two key operating variables that influence these performance criteria are the mean scaffold pore size and flow-rate. Using cyclooxygenase-2 and osteopontin gene expression levels as surrogate indicators of osteogenesis, we employed the "windows of operation" methodology to rapidly identify feasible operating ranges for the mean scaffold pore size and flow-rate that achieved user-defined levels of performance for cell detachment and differentiation. Incorporation of such tools into the tissue engineer's armory will hopefully yield a greater understanding of the highly complex systems used and help aid decision making in future translation of products from the bench top to the market place. PMID:22627891

McCoy, Ryan J; O'Brien, Fergal J

2012-06-11

65

Ecology of estuaries  

SciTech Connect

This book is a summary of information available on estuarine ecology, that reviews concepts and problems of estuaries and assesses the value of these coastal systems. It investigates such topics as water circulation and mixing, trace elements, nutrients, organic matter, and sedimentary processes, with reviews on more than two decades of intense study. Chapters reflect contributions from a variety of interdisciplinary sciences including botany, chemistry, ecology, geology, physics, and zoology.

Kennish, M.J.

1986-01-01

66

North Sea estuaries  

Microsoft Academic Search

Studies of the North Sea in the past two decades have shown that its estuaries and associated areas, such as the Wadden Sea,\\u000a are important as nursery grounds for young fish and as feeding grounds for seabirds. These same areas are also those most\\u000a likely to be affected by the highest inputs and concentrations of contaminants. The development of agriculture,

Donald S. McLusky

2001-01-01

67

Feasibility study of air-breathing turbo-engines for horizontal take-off and landing space plane  

Microsoft Academic Search

Various concepts of air-breathing engines (ABEs) that could be used for a horizontal take-off and landing SSTO vehicle are investigated. The performances (with respect to thrust and the specific fuel consumption) of turboengines based on various technologies, including a turbojet with and without afterburner (TJ), turboramjet, and air-turbo-ram jet engines are compared. The mission capabilities of these ABEs for SSTO

M. Minoda; K. Sakata; T. Tamaki; T. Saitoh; A. Yasuda

1989-01-01

68

Historic Habitat Opportunities and Food-Web Linkages of Juvenile Salmon in the Columbia River Estuary, Annual Report of Research  

Microsoft Academic Search

In 2002 with support from the U.S. Army Corps of Engineers (USACE), an interagency research team began investigating salmon life histories and habitat use in the lower Columbia River estuary to fill significant data gaps about the estuary's potential role in salmon decline and recovery . The Bonneville Power Administration (BPA) provided additional funding in 2004 to reconstruct historical changes

Daniel L. Bottom; Charles A. Simenstad; Lance Campbell

2009-01-01

69

Historic Habitat Opportunities and Food-Web Linkages of Juvenile Salmon in the Columbia River Estuary, Annual Report of Research.  

National Technical Information Service (NTIS)

In 2002 with support from the U.S. Army Corps of Engineers (USACE), an interagency research team began investigating salmon life histories and habitat use in the lower Columbia River estuary to fill significant data gaps about the estuary's potential role...

C. A. Simenstad D. L. Bottom L. Campbell

2009-01-01

70

Ecology of estuaries: Anthropogenic effects  

Microsoft Academic Search

Estuaries and near-shore oceanic water are subjected to a multitude of human wastes. The principal objective of this book is to examine anthropogenic effects on estuaries, and it focuses primarily on contaminants in coastal systems. Covered within various chapters are the following topics: waste disposal strategies; definition and classification of pollutants (including organic loading, oil pollution, polynuclear aromatic hydrocarbons; chlorinated

Kennish; Michael J. Kennish

1992-01-01

71

Delaware Estuary situation reports. Emergency response: How do emergency management officials address disasters in the Delaware Estuary  

SciTech Connect

From hurricanes and other natural threats to oil spills and other manmade emergencies, the Delaware Estuary has experienced a variety of disasters over the years. The toll that these events take on the estuary and those who live on its shores depends largely upon the degree of emergency preparedness, speed of response, and effectiveness of recovery operations. In Emergency Response: How Do Emergency Management Officials Address Disasters in the Delaware Estuary, the latest addition to its Delaware Estuary Situation Report series, the University of Delaware Sea Grant College Program defines emergency management; examines the roles that the Coast Guard, Army Corps of Engineers, and Environmental Protection Agency play in an emergency; and reviews how each of these federal agencies operated during an actual disaster--the 1985 Grand Eagle oil spill. The report was written by Dr. Richard T. Sylves, a professor of political science at the University of Delaware. Sylves has been studying emergency management for the past 15 years, with special emphasis on oil spill preparedness and response in the Mid-Atlantic Region. The Delaware Estuary Situation Report is 12 pages long and contains maps and photographs, as well as a detailed account of response and recovery operations undertaken during the Grand Eagle oil spill. A comparison of the 1985 Grand Eagle spill and the 1989 Presidente Rivera spill also is included.

Sylves, R.T.

1991-01-01

72

Feasibility study of air-breathing turbo-engines for horizontal take-off and landing space plane  

SciTech Connect

Various concepts of air-breathing engines (ABEs) that could be used for a horizontal take-off and landing SSTO vehicle are investigated. The performances (with respect to thrust and the specific fuel consumption) of turboengines based on various technologies, including a turbojet with and without afterburner (TJ), turboramjet, and air-turbo-ram jet engines are compared. The mission capabilities of these ABEs for SSTO and TSTO vehicles is examined in terms of the ratio of the effective remaining weight (i.e., the weight on the orbit) to the take-off gross weight, using two-dimensional flight analysis. It was found that the dry TJ with the turbine inlet temperature 2000 C is one of the most promising candidates for the propulsion system of the SSTO vehicle, because of its small weight and high specific impulse. 6 refs.

Minoda, M.; Sakata, K.; Tamaki, T.; Saitoh, T.; Yasuda, A.

1989-01-01

73

Dissolved oxygen in two Oregon estuaries: Importance of the ocean-estuary connection - March 2011  

EPA Science Inventory

We examined the role of the ocean?estuary connection in influencing periodic reductions in dissolved oxygen (DO) levels in Yaquina and Yachats estuaries, Oregon, USA. In the Yaquina Estuary, there is close coupling between the coastal ocean and the estuary. As a result, low DO w...

74

Dissolved oxygen in two Oregon estuaries: The importance of the ocean-estuary connection  

EPA Science Inventory

We examined the role of the ocean ?estuary connection in influencing periodic reductions in dissolved oxygen (DO) levels in Yaquina and Yachats estuaries, Oregon, USA. In the Yaquina Estuary, there is close coupling between the coastal ocean and the estuary. As a result, low DO ...

75

Dissolved oxygen in two Oregon estuaries: Importance of the ocean-estuary connection  

EPA Science Inventory

We examined the role of the ocean ?estuary connection in influencing periodic reductions in dissolved oxygen (DO) levels in Yaquina and Yachats estuaries, Oregon, USA. In the Yaquina Estuary, there is close coupling between the coastal ocean and the estuary. As a result, low DO ...

76

A trophic model for the Danshuei River Estuary, a hypoxic estuary in northern Taiwan  

Microsoft Academic Search

The estuary of the Danshuei River, a hypoxic subtropical estuary, receives a high rate of untreated sewage effluent. The Ecopath with Ecosim software system was used to construct a mass-balanced trophic model for the estuary, and network analysis was used to characterize the structure and matter flow in the food web. The estuary model was comprised of 16 compartments, and

Hsing-Juh Lin; Kwang-Tsao Shao; Rong-Quen Jan; Hwey-Lian Hsieh; Chang-Po Chen; Li-Yung Hsieh; Yi-Ting Hsiao

2007-01-01

77

Estuary wader capacity following severe weather mortality.  

National Technical Information Service (NTIS)

The building of a tidal power barrage across an estuary may lead to substantial changes in its ecology. Many of Britain's estuaries hold internationally important numbers of waders. Careful consideration, therefore, needs to be given to the likely effects...

J. A. Clark S. R. Baillie N. A. Clark R. H. W. Langston

1993-01-01

78

Hampton-Seabrook Estuary Habitat Restoration Compendium.  

National Technical Information Service (NTIS)

The Hampton-Seabrook Estuary Habitat Restoration Compendium (HSEHRC) is a compilation of information on the historic and current distributions of salt marsh and sand dune habitats and diadromous fishes within the Hampton-Seabrook Estuary watershed. These ...

A. L. Eberhardt D. M. Burdick

2009-01-01

79

PECONIC ESTUARY EELGRASS HABITAT CRITERIA STUDY  

EPA Science Inventory

PECONIC ESTUARY EELGRASS HABITAT CRITERIA STUDY The main objective of this study is to develop criteria for eelgrass habitat establishment and persistence within the Peconic Estuary utilizing various environmental analyses. The Program evaluated water and sediment quality data to...

80

Estuaries and Clean Water Act of 2000  

NSDL National Science Digital Library

The Office of Water at the Environmental Protection Agency has posted online this document on the new Estuaries and Clean Water Act of 2000. Available in .pdf format, the document summarizes the Act, which emphasizes restoration of estuary habitat.

81

EXHIBIT OF EMPACT ESTUARY MONITORING HANDBOOKS  

EPA Science Inventory

Related EMPACT documents were displayed at the National Estuary Day Celebration held in Washington, DC, September 30-Octuber 4, 2002. The estuary monitoring technology transfer handbooks displayed were prepared based on information and monitoring technologies developed from selec...

82

Nakdong Estuary and Land Reclamation Morphological Aspects.  

National Technical Information Service (NTIS)

The construction of the barrage will change the flow conditions in the entire estuary which will interfere in the present equilibrium between channel dimensions and flow conditions. Consequently, morphological changes in the estuary have to be taken into ...

W. D. Eysink

1983-01-01

83

Estuaries: Where Rivers Meet the Sea  

NSDL National Science Digital Library

Take your students on an EstuaryLive telecast! EstuaryLive brings free, live internet field trips in four different estuaries around the country, right to your classroom. These online field trips are the next best thing to an actual trip to an estuary, providing students with an exciting and new way to learn about unique estuarine ecosystems. The site also includes archived webcasts and teacher resources including classroom activities and a glossary.

84

Estuaries: Where Rivers Meet the Sea  

NSDL National Science Digital Library

Take your students on an EstuaryLive telecast! EstuaryLive brings free, live internet field trips in four different estuaries around the country, right to your classroom. These online field trips are the next best thing to an actual trip to an estuary, providing students with an exciting and new way to learn about unique estuarine ecosystems. The site also includes archived webcasts and teacher resources including classroom activities and a glossary.

2011-05-16

85

PECONIC ESTUARY STORMWATER ASSESSMENT AND PLANNING TOOL  

EPA Science Inventory

PECONIC ESTUARY STORMWATER ASSESSMENT AND PLANNING TOOL Horsley & Witten, Inc. was contracted by the Peconic Estuary Program to create a Regional Stormwater Runoff Management Plan designed to mitigate loadings of fecal coliform bacteria and nitrogen to the Peconic Estuary. The pu...

86

Fish use of the Elwha estuary  

Microsoft Academic Search

The fish use of three main areas (east, west, and impounded west sections) of the Elwha estuary was assessed using standard seining techniques from March-September 2007. Species diversity, richness, and evenness were all highest in the connected section of the west estuary which constitutes only 20% of the total Elwha estuary. Further, over 60% of total fish, 90% of salmonids,

J. Anne; J. Schilke; R. Paradis; D. Barry; P. Crain

2008-01-01

87

Ecotone or Ecocline: Ecological Boundaries in Estuaries  

Microsoft Academic Search

Two main ecological boundaries, ecotone and ecocline, have been defined in landscape ecology. At this scale, the estuary represents a boundary between rivers and the sea, but there has been no attempt to fit empirical data for estuaries to these boundary models. An extensive data set from the Thames estuary was analysed using multivariate techniques and species-range analysis, in order

M. J Attrill; S. D Rundle

2002-01-01

88

Feasibility study for an engineering concept of a stainless steel/copper divertor plate protected by W-5 Re alloy or graphite armor  

SciTech Connect

The latest Joint Research Centre (JRC)-Ispra proposal is presented to support the design of a divertor concept that has long been considered the most crucial component of the plasma impurity control system for the Next Europen Torus (NET) tokamak fusion reactor. Because of the harsh tokamak environment, the divertor panel is the plasma facing component that suffers the most severe loading conditions, such as high thermal stresses, thermal fatigue, severe erosion rates and neutron damage. An analysis of a new divertor panel concept has evolved from the previous studies carried out at JRC-Ispra. The materials considered in this study are AISI 316 stainless steel for the cooling tubes, pure copper for the heat sink, and W-5 Re alloy or graphite for the protective armor. The panel is cooled by pressurized water circulation in U-tubes. A preliminary thermo-hydraulic analysis has been carried out to evaluate a set of reference parameters, such as optimum coolant velocity, maximum outlet water temperature, convective heat exchange coefficient, and the expected pressure drops in the channels. Thermal and mechanical calculations, performed by using the finite element technique, showed encouraging results about the engineering feasibility of the pressure boundary of the divertor for loading conditions similar to those of NET double null, assumed as the reference mainframe.

Renda, V.; Federici, G.; Papa, L.

1988-03-01

89

Viability of Rehabilitated Apartment Buildings: A Feasibility Study Method for Building Rehabilitation Projects Developed by Action Research, Acta Polytechnica Scandinavica. Civil Engineering and Building Construction Series No. 111.  

National Technical Information Service (NTIS)

The rehabilitation of rental apartment buildings has often been expensive in Finland. The aim of the research was to develop a feasibility-study method for building rehabilitation projects. The feasibility-study method was developed and tested by applying...

A. Saari

1998-01-01

90

Carbon dioxide emission from european estuaries  

PubMed

The partial pressure of carbon dioxide (pCO2) in surface waters and related atmospheric exchanges were measured in nine European estuaries. Averaged fluxes over the entire estuaries are usually in the range of 0.1 to 0.5 mole of CO2 per square meter per day. For wide estuaries, net daily fluxes to the atmosphere amount to several hundred tons of carbon (up to 790 tons of carbon per day in the Scheldt estuary). European estuaries emit between 30 and 60 million tons of carbon per year to the atmosphere, representing 5 to 10% of present anthropogenic CO2 emissions for Western Europe. PMID:9774261

Frankignoulle; Abril; Borges; Bourge; Canon; Delille; Libert; Theate

1998-10-16

91

Valuing environmental water pulses into the Incomati estuary: Key to achieving equitable and sustainable utilisation of transboundary waters  

NASA Astrophysics Data System (ADS)

Upstream developments in the Incomati river basin, shared by South Africa, Swaziland and Mozambique, have altered downstream flows significantly. The frequency of small floods into the estuary has been reduced dramatically. This change in the flow regime has impacted on the state of the environment downstream, and the Incomati estuary in particular. The estuary requires fresh water pulses that naturally occur, and the resulting seasonal flooding of the plains. Resource-poor rural households depend on the goods and services that the estuary and flood plains provide such as wood, charcoal, building materials, fish and shrimp, wetland farming, and tourism. Alteration of the flow regime into the estuary has a negative impact on the state of the environment and hence on the goods and services the estuary yields; a phenomenon the people living near the estuary are keenly aware of. The article estimates the value of the goods and services that the estuary currently provides, that is under the conditions of a changed flow regime. A linear relationship is then assumed between fresh water pulses into the estuary and the goods and services it provides, so that the order of magnitude of the economic value of fresh water pulses into the estuary may be approximated. Various development scenarios in the Incomati basin are then considered, that have different upstream and downstream impacts on water availability, and the basin-wide benefits and costs are compared. The paper concludes that the principle of sharing the benefits derived from the water resources, rather than the water itself, as proposed by authors such as [Sadoff, C.W., Grey, D., 2002. Beyond the river: the benefits of cooperation on international rivers. Water Policy 4, 389 403], may be a feasible approach only if the less tangible benefits and functions, especially those of the environment, are assigned an appropriate value and corresponding priority.

Sengo, D. José; Kachapila, Albert; Zaag, Pieter Van Der; Mul, Marloes; Nkomo, Sakhiwe

92

DELAWARE ESTUARY A MANAGEMENT PLAN FOR THE DELAWARE ESTUARY  

EPA Science Inventory

Wise conservation and management of the Delaware Estuary is arguably the most important cooperative environmental initiative ever jointly undertaken by the States of New Jersey, Pennsylvania, and Delaware. While much has been accomplished over the past few decades to improve wate...

93

Estuary program primer. National Estuary Program. Draft report  

SciTech Connect

The manual provides an overview of the National Estuary Program and its functions and management structure. The manual also describes the Comprehensive Conservation and Management Plan, a framework that can be used to help in prevention and control of pollution, land over-use, and man-environment conflicts.

Not Available

1987-10-01

94

WERF MACT Feasibility Study Report.  

National Technical Information Service (NTIS)

This study was undertaken to determine the technical feasibility of upgrading the Waste Experimental Reduction Facility (WERF) at the Idaho National Engineering and Environmental Laboratory to meet the offgas emission limits proposed in the Maximum Achiev...

B. Bonnema D. Moser J. Riedesel K. Kooda K. Liekhus

1998-01-01

95

SSPA Equipment Engineering Feasibility Report  

SciTech Connect

In response to a demanding reactor conversion schedule, construction of the Shielded Sample Preparation Area (SSPA) was initiated in 2010 to augment the existing capabilities of the Hot Fuel Examination Facility (HFEF). While HFEF is and will remain the workhorse for post irradiation sample preparation, there is currently a large backlog of Post-Irradiation Examination (PIE) experiments caused by numerous competing projects (this backlog is expected to continue for the foreseeable future). HFEF, in its present configuration also lacks the ability to prepare samples suitable for several of the tests that have been identified for the successful conclusion of the RERTR program; these samples require fine detail machining of irradiated fuel plates.

N.E. Woolstenhulme; C.R. Clark

2011-09-01

96

The Value of Healthy Estuaries  

NSDL National Science Digital Library

The article explores why healthy estuaries are critical to humans and wildlife: supporting both commercial and recreational fisheries, treating waste and runoff, protecting coastal areas from natural hazards, connect bodies of water for transportation, and nurturing a balance of the food web

Robert Christian (East Carolina University;)

2009-03-15

97

The Value of Healthy Estuaries  

NSDL National Science Digital Library

Healthy estuaries are critical to humans and wildlife. They provide food, supporting both commercial and recreational fisheries, treat waste and runoff to maintain water quality, protect coastal areas from natural hazards, connect bodies of water for transportation and marine operations, and nurture a balance of the food web upon which all life depends.

Robert Christian (Thomas Harriot College of Arts and Sciences;)

2009-03-22

98

Food Webs in an Estuary.  

ERIC Educational Resources Information Center

|The Maryland Marine Science Education Project has produced a series of mini-units in marine science education for the junior high/middle school classroom. This unit focuses on food chains in an estuary. Although the unit specifically treats the Chesapeake Bay, it may be adapted for use with similar estuarine systems. In addition, the unit may be…

Dunne, Barbara B.

99

Simulated Sampling of Estuary Plankton  

ERIC Educational Resources Information Center

|To find out about the microscopic life in the valuable estuary environment, it is usually necessary to be near the water. This dry lab offers an alternative, using authentic data and a simulation of plankton sampling. From the types of organisms found in the sample, middle school students can infer relationships in the biological and physical…

Fortner, Rosanne W.; Jenkins, Deborah Bainer

2009-01-01

100

DENSITY-DEPENDENT IMPACTS OF BIOIRRIGATION BY THE BURROWING SHRIMP UPOGEBIA PUGETTENSIS ON BENTHIC FLUXES AND POREWATER SOLUTE DISTRIBUTIONS IN PACIFIC NORTHWEST ESTUARIES  

EPA Science Inventory

Burrowing thalassinid shrimp are major ecosystem engineering species of Pacific estuaries and can structure the physical, chemical, and biotic properties of sediments. Feeding and burrow irrigation by benthic organisms can increase the remineralization rates of organic material (...

101

Carbon dioxide emissions from Indian monsoonal estuaries  

NASA Astrophysics Data System (ADS)

Estuaries are known to be strong source for atmospheric CO2, however, little information is available from Indian estuaries. In order to quantify CO2 emissions from the Indian estuaries, samples were collected at 27 estuaries all along the Indian coast during discharge (wet) period. The emissions of CO2 to the atmosphere from Indian estuaries were 4-5 times higher during wet than dry period. The pCO2 ranged between ˜300 and 18492 ?atm which are within the range of world estuaries. The mean pCO2 and particulate organic carbon (POC) showed positive relation with rate of discharge suggesting availability of high quantities of organic matter that led to enhanced microbial decomposition. The annual CO2 fluxes from the Indian estuaries, together with dry period data available in the literature, amounts to 1.92 TgC which is >10 times less than that from the European estuaries. The low CO2 fluxes from the Indian estuaries are attributed to low flushing rates and less human settlements along the banks of the Indian estuaries.

Sarma, V. V. S. S.; Viswanadham, R.; Rao, G. D.; Prasad, V. R.; Kumar, B. S. K.; Naidu, S. A.; Kumar, N. A.; Rao, D. B.; Sridevi, T.; Krishna, M. S.; Reddy, N. P. C.; Sadhuram, Y.; Murty, T. V. R.

2012-02-01

102

Feasibility Analysis in Small Hydropower Planning.  

National Technical Information Service (NTIS)

The Hydrologic Engineering Center, Corps of Engineers, has prepared a manual entitled 'Feasibility Studies for Small Scale Hydropower Additions'. The manual provides technical data and procedural guidance for the systematic appraisal of the viability of p...

D. W. Davis B. W. Smith

1979-01-01

103

MAPPING BATHYMETRY AND BOTTOM TYPE IN A SHALLOW ESTUARY  

EPA Science Inventory

Bathymetry and bottom type are important in characterizing estuaries and their ecology but hard to map, especially in shallow estuaries. Acoustic backscattering was used to remotely sense these properties in the shallow Slocums River Estuary of Massachusetts. Acoustic pulses were...

104

Lower Columbia River Estuary Partnership: Habitat Restoration Case Studies.  

National Technical Information Service (NTIS)

The Estuary Partnership was established in 1995, when the lower Columbia River and estuary were accepted into the US Environmental Protection Agency National Estuary Program. As the coordinating body for efforts to enhance and restore the lower Columbia R...

2006-01-01

105

Carbon dioxide emissions from Indian monsoonal estuaries  

NASA Astrophysics Data System (ADS)

The oceans act as a net sink for atmospheric CO2, however, the role of coastal bodies on global CO2 fluxes remains unclear due to lack of data. The estimated absorption of CO2 from the continental shelves, with limited data, is 0.22 to 1.0 PgC/y, and of CO2 emission by estuaries to the atmosphere is 0.27 PgC/y. The estimates from the estuaries suffer from large uncertainties due to large variability and lack of systematic data collection. It is especially true for Southeast Asian estuaries as the biogeochemical cycling of material are different due to high atmospheric temperature, seasonality driven by monsoons, seasonal discharge etc. In order to quantify CO2 emissions from the Indian estuaries, samples were collected at 27 estuaries all along the Indian coast during discharge wet and dry periods. The emissions of CO2 to the atmosphere from Indian estuaries were 4-5 times higher during wet than dry period. The pCO2 ranged between ~300 and 18492 microatm which were within the range of world estuaries. The mean pCO2 and particulate organic carbon (POC) showed positive relation with rate of discharge suggesting availability of high quantities of organic matter that led to enhanced microbial decomposition. The annual CO2 fluxes from the Indian estuaries, together with dry period data available in the literature, amounts to 1.92 TgC which is >10 times less than that from the European estuaries. The low CO2 fluxes from the Indian estuaries are attributed to low flushing rates and less human settlements along the banks of the Indian estuaries.

Sarma Vedula, VSS

2012-07-01

106

Facilitation of the Estuary/Ocean Subgroup for Federal Research, Monitoring, and Evaluation, FY10 Annual Report  

SciTech Connect

The Estuary/Ocean Subgroup (EOS) is part of the research, monitoring, and evaluation (RME) effort that the Action Agencies (Bonneville Power Administration, U.S. Army Corps of Engineers, U.S. Bureau of Reclamation) developed in response to obligations arising from the Endangered Species Act as applied to operation of the Federal Columbia River Power System (FCRPS). The goal of the EOS project is to facilitate activities of the estuary/ocean RME subgroup as it coordinates design and implementation of federal RME in the lower Columbia River and estuary. The EOS is one of multiple work groups in the federal research, monitoring, and evaluation (RME) effort developed in response to responsibilities arising from the Endangered Species Act as a result of operation of the FCRPS. The EOS is tasked by NOAA Fisheries and the Action Agencies to design and coordinate implementation of the federal RME plan for the lower Columbia River and estuary, including the plume.

Johnson, Gary E.

2010-10-26

107

NEW HAMPSHIRE'S ESTUARIES, THE STATE OF  

EPA Science Inventory

The State of the New Hampshire Estuary Report describes the region's valuable natural resources, explains how natural resources are linked to the cultural and economic well being of New Hampshire, and identifies threats to these resources. This State of the Estuaries Report summa...

108

NEW HAMPSHIRE ESTUARIES PROJECT MANAGEMENT PLAN  

EPA Science Inventory

This Comprehensive Conservation and Management Plan of the New Hampshire Estuaries Project presents a broad framework and specific list of actions to protect and enhance the environmental quality of the estuaries of the State of New Hampshire. It is intended to be a guide for all...

109

Estuaries: Where Rivers Meet the Sea  

NSDL National Science Digital Library

This website is the educational site for NOAA's National Estuarine Research Reserve System (NERRS), managed and maintained by NERRS education staff. This site provides, primarily, an avenue for elementary, middle and high school students, and their teachers, to learn more about estuaries, research, and explore NOAAâs âliving laboratoriesâ - the National Estuarine Research Reserves. The Estuary Video Gallery offers a collection of short video clips. The main content themes include relationships between estuaries and humans, life in an estuary, impacts of society upon estuaries and current research and equipment used in monitoring estuaries in video format. Also included are E-Live Backpacks designed to extend and enhance specific Estuaries 101 High-School Curriculum activities by using video clips from our Video Gallery, and relating them to important estuary principles and concepts. Students are asked to review the materials in the E-Live Backpacks, to construct their own compelling questions, actively research those questions, and share their learning through final products. By going through these steps, you will lead students through a project-based learning experience. this site is also available in Spanish.

110

MARSH LOSS IN NANTICOKE ESTUARY, CHESAPEAKE BAY  

Microsoft Academic Search

Marsh loss in the Nanticoke estuary dates from the 1920s. Since 1938 overall rate of loss has averaged 49.6 ha annually, with rates increasing down estuary. Most losses have occurred in submerged upland marshes; tidal freshwater marshes are stable. Interior ponding has been the primary mechanism of loss. Rising water levels are postulated to be the underlying force behind marsh

MICHAEL S. KEARNEYO; RUSSELL E. GRACE

1988-01-01

111

Dissolved oxygen in two Oregon estuaries: The importance of the ocean-estuary connection - May 16, 2011  

EPA Science Inventory

We examined the role of the ocean ?estuary connection in influencing periodic reductions in dissolved oxygen (DO) levels in Yaquina and Yachats estuaries, Oregon, USA. In the Yaquina Estuary, there is close coupling between the coastal ocean and the estuary. As a result, low DO ...

112

An Examination of the Influence of Freshwater Canal Discharges on Salinity in Selected Southeastern Florida Estuaries.  

National Technical Information Service (NTIS)

Monthly determinations of surface and bottom water salinity were made within the canal (or stream) estuary complexes of six southeastern Florida coastal zones (St. Lucie River and Estuary, Loxahatchee River and Estuary, West Palm Beach Canal and Estuary, ...

B. I. Birnhak

1974-01-01

113

Long-term (1842-2006) morphological change and equilibrium state of the Changjiang (Yangtze) Estuary, China  

NASA Astrophysics Data System (ADS)

The 165 year morphological evolution of the Changjiang (Yangtze) Estuary and its long-term equilibrium characteristics have been investigated using 16 selected maritime charts from 1842 to 2006. These charts were digitized and analyzed with a GIS to provide quantitative estimates of geomorphologic changes below selected bottom elevations. The results show that the Changjiang Estuary has experienced overall erosion over this 165 year period, having been affected by several large erosion and deposition episodes. It is found that the overall volume changes are less than 10% and aspect ratios of <5 have increased from 2% to ca. 30%. During this period, both coastlines and thalwegs have become straighter and more aligned with the propagation direction of offshore tidal current, indicating that the estuary is approaching dynamic equilibrium. Based on variations of aspect ratios and thalweg movements, five types of stable channels were identified. Significant topographical changes, including infilling after 1958 and erosion after 1980, are principally associated with engineering work around the estuary and a reduction in sediment supply. Although human influence only notably occurred at certain locations in the estuary, such as upstream node of an estuary, it had a significant impact on the overall geomorphologic evolution. In addition to these anthropogenic effects, freshwater flow, sediment discharges, tide propagation and Coriolis force are also found to play important roles in channel development within the estuary. By contrast, changes in other factors such as sea level changes and wave climate were considered to be of relatively minor importance in the morphological evolution process of the estuary.

Wang, Yonghong; Dong, Ping; Oguchi, Takashi; Chen, Shenliang; Shen, Huanting

2013-03-01

114

PAPER Special Issue on Special Issue on Knowledge-Based Software Engineering A Method to Develop Feasible Requirements for Java Mobile Code Application  

Microsoft Academic Search

SUMMARY We propose a method for analyzing trade-off between an environment where a Java mobile code application is running and requirements for the application. In particular, we focus on the security-related problems that originate in low-level security policy of the code-centric style of the access control in Java runtime. As the result of this method, we get feasible re- quirements

Haruhiko KAIYA; Kouta SASAKI; Kenji KAIJIRI

115

United States Air Force 611th Air Support Group/Civil Engineering Squadron Elmendorf AFB, Alaska. Remedial investigation and feasibility study. Bullen Point Radar Installation, Alaska. Final report  

SciTech Connect

The United States Air Force (Air Force) has prepared this Remedial investigation/Feasibility Study (RI/FS) report as part of the Installation Restoration Program (IRP) to present results of RI/FS activities at five sites at the Bullen Point radar installation. The IRP provides for investigating, quantifying, and remediating environmental contamination from past waste management activities at Air Force installations throughout the United States.

Karmi, S.

1996-03-18

116

Evaluating Cumulative Ecosystem Response to Restoration Projects in the Columbia River Estuary, Annual Report 2005  

SciTech Connect

This report is the second annual report of a six-year project to evaluate the cumulative effects of habitat restoration projects in the Columbia River Estuary, conducted by Pacific Northwest National Laboratory's Marine Sciences Laboratory, NOAA's National Marine Fisheries Service Pt. Adams Biological Field Station, and the Columbia River Estuary Study Taskforce for the US Army Corps of Engineers. In 2005, baseline data were collected on two restoration sites and two associated reference sites in the Columbia River estuary. The sites represent two habitat types of the estuary--brackish marsh and freshwater swamp--that have sustained substantial losses in area and that may play important roles for salmonids. Baseline data collected included vegetation and elevation surveys, above and below-ground biomass, water depth and temperature, nutrient flux, fish species composition, and channel geometry. Following baseline data collection, three kinds of restoration actions for hydrological reconnection were implemented in several locations on the sites: tidegate replacements (2) at Vera Slough, near the city of Astoria in Oregon State, and culvert replacements (2) and dike breaches (3) at Kandoll Farm in the Grays River watershed in Washington State. Limited post-restoration data were collected: photo points, nutrient flux, water depth and temperature, and channel cross-sections. In subsequent work, this and additional post-restoration data will be used in conjunction with data from other sites to estimate net effects of hydrological reconnection restoration projects throughout the estuary. This project is establishing methods for evaluating the effectiveness of individual projects and a framework for assessing estuary-wide cumulative effects including a protocol manual for monitoring restoration and reference sites.

Diefenderfer, Heida L.; Thom, Ronald M.; Borde, Amy B.; Roegner, G. C.; Whiting, Allan H.; Johnson, Gary E.; Dawley, Earl; Skalski, John R.; Vavrinec, John; Ebberts, Blaine D.

2006-12-20

117

PECONIC ESTUARY PROGRAM TIDAL CREEK STUDY  

EPA Science Inventory

EEA evaluated ten tidal creeks throughout the Peconic Estuary representing a wide range of watershed variables. Primary focus was directed towards the collection and analysis of the macrobenthic invertebrate communities of these ten tidal creeks. Analysis of the macrobenthic comm...

118

EPA'S BENTHIC HABITAT DATA FOR YAQUINA ESTUARY  

EPA Science Inventory

Scientists at EPA's National Health and Environmental Effects Research Laboratory, Western Ecology Division (WED) have been studying seafloor (benthic) habitats in Yaquina estuary for several years. Those studies were conducted as parts of several research projects, including: e...

119

ECOLOGICAL CONDITION OF SOUTH FLORIDA ESTUARIES  

EPA Science Inventory

An assessment of the ecological condition of south Florida estuaries based on regional probabilistic monitoring was conducted during the summer of 1995. Samples and data were collected on water and sediment quality, benthos, and fish tissue contaminants. Elevated concentrations o...

120

Algal Nutrient Studies of the Potomac Estuary.  

National Technical Information Service (NTIS)

The nutrient requirements of the phytoplankton of the Potomac Estuary were studied during the summer of 1977 employing the following laboratory tests: NH4(t)-N uptake, alkaline phosphatase enzyme activity; extractable surplus orthophosphate; tissue analys...

J. L. Slayton E. R. Trovato

1977-01-01

121

Columbia River Estuary Regional Management Plan, 1979.  

National Technical Information Service (NTIS)

The Columbia River Estuary Regional Management Plan contains the following information: Part I, Background: Explains how the plan may be used, how public and private interests were involved in developing the plan, what issues and problems were central in ...

1979-01-01

122

The Peel Inlet-Harvey Estuary Study.  

ERIC Educational Resources Information Center

|Describes how the department of physics of the Western Australian Institute of Technology (WAIT) has been involved in the Peel Inlet-Harvey Estuary study. An appendix which presents the departmental approach to curriculum matters is also included. (HM)|

Walker, Warren; Black, Ronald

1979-01-01

123

Water renewal timescales in the Scheldt Estuary  

NASA Astrophysics Data System (ADS)

Using the concepts of the Constituent-oriented Age and Residence time Theory (CART), we compute timescales related to the water renewal in the Scheldt Estuary (The Netherlands/Belgium). Three different timescales are used to better understand and characterize the dynamics of the estuary: the age of the renewing water, the residence time and the exposure time. The residence time is the time taken by a water parcel to leave the estuary for the first time while the exposure time is the total time spent by a water parcel in the estuary including re-entries. The age of a renewing water parcel is defined as the time elapsed since it entered the estuary. The renewing water was split into three types: the water originating from the sea, the water originating from the upstream fresh tidal rivers and the water originating from the different canals and docks connected to the estuary. Every timescale is computed at any time and position by means of the finite-element, unstructured-mesh model SLIM. This results in movies of the timescale fields (shown as Supplementary material), allowing a detailed analysis of their spatial and temporal variabilities. The effect of the M2 tide and the discharge regime (winter, summer or average situation) on the timescales is also investigated.Tidally-averaged timescales vary little over the width of the estuary and hence exhibit a virtually one-dimensional behaviour. However, around these average values, the timescales can vary hugely over a tidal cycle, with amplitudes that significantly depend on the space coordinates. The reason thereof has yet to be elucidated. These results underscore the need for two- or three-dimensional models with high temporal resolution for investigating the dynamics of the Scheldt Estuary.

de Brye, Benjamin; de Brauwere, Anouk; Gourgue, Olivier; Delhez, Eric J. M.; Deleersnijder, Eric

2012-06-01

124

Residual Exchange Flows in Subtropical Estuaries  

Microsoft Academic Search

Observations of residual exchange flows at the entrance to four subtropical estuaries, two of them semiarid, indicate that\\u000a these flows are mainly tidally driven, as they compare favorably with theoretical patterns of tidal residual flows. In every\\u000a estuary examined, the tidal behavior was that of a standing or near-standing wave, i.e., tidal elevation and tidal currents\\u000a were nearly in quadrature.

Arnoldo Valle-Levinson; Guillermo Gutierrez de Velasco; Armando Trasviña; Alejandro J. Souza; Reginaldo Durazo; Ashish J. Mehta

2009-01-01

125

Iodine speciation in the Nile River estuary  

Microsoft Academic Search

During high- and low-flood periods, surface and bottom water samples were collected along the Nile River estuary for the voltammetric determination of dissolved iodine species. Iodine occurs in the estuary as iodate, iodide and organic iodine. Total iodine increases with salinity, showing a source feature in surface and bottom waters during high-flow indicating iodine input. During low-flow, total iodine showed

M. A. R Abdel-Moati

1999-01-01

126

Methane distribution in European tidal estuaries  

Microsoft Academic Search

Methane concentrations have been measured along salinity profilesin nine tidal estuaries in Europe (Elbe, Ems, Thames, Rhine,Scheldt, Loire, Gironde, Douro and Sado). The Rhine, Scheldt andGironde estuaries have been studied seasonally. A number ofdifferent methodologies have been used and they yieldedconsistent results. Surface water concentrations ranged from0.002 to 3.6 µM, corresponding to saturation ratios of 0.7 to1580 with a median

Jack J. Middelburg; Joop Nieuwenhuize; Niels Iversen; Nana Høgh; Hein de Wilde; Wim Helder; Richard Seifert; Oliver Christof

2002-01-01

127

Mixing in the Amazon estuary  

NASA Astrophysics Data System (ADS)

The research area of this work is located at the estuary of the Amazon River (Brazil), near the river mouth. The results of air movement analysis on the surface atmospheric circulation over the Mouth of the Amazonas River, salinity and temperature measures as well as measurements of currents, carried out along a longitudinal section in the navigation canal region of the Northern Bar of the Amazon River (Barra Norte do Rio Amazonas) in June 2006, during the river flood season in the quadrature tide. The dynamics effects affect hydrodynamic,meteorological and hydrographical parameters at the river mouth. The conclusion drawn include that: a) the saline wedge-type stratification can be detected approximately 100km away from the mouth of the Amazon River during the end of the rainy season in the quadrature tide; b) probably, at the Amazon estuary the quadrature entrainment processes are dominant and they are the ones responsible for increased salinity detected in the surface layer, whereas turbulence scattering mixing is not so important. c) The large flow of fresh water from the Amazon River at the end of the rainy season implies the displacement of the saline front position over the internal Amazon continental platform, and d) The tidal wave shows a positive asymmetry in the canal, with floods lasting less than in the ebb tide. This asymmetry decreases towards the ocean, eventually becoming reversed in the presence of a saline wedge. The speeds, however, have a negative asymmetry, with more intense ebb tides, due to the river flow and is more evident by the existence of quadrature tides.

Bezerra, M. O.

2010-05-01

128

Design and implementation of saltwater intrusion forewarning system in Pearl River Estuary based on WebGIS  

Microsoft Academic Search

In recent years, increasing marine intrusion into the Pearl River Estuary (PRE) of South China, poses a great threat to water supply of Pearl River Delta and causes drinking water problems of 15 million people. To reduce the influence of saltwater intrusion, engineering measures can be adopted, such as improving the water supply project and the management of water resources

Hongli Li; Ligang Fang; Zhaobin Liu

2010-01-01

129

United States Air Force 611th Air Support Group Civil Engineering Squadron, Elmendorf AFB, Alaska. Remedial investigation and feasibility study Point Lay Radar Installation, Alaska. Final report  

SciTech Connect

The United States Air Force (Air Force) has prepared this Remedial Investigation/Feasibility Study (RI/FS) report to present the results of RI/FS activities at four sites located at the Point Lay radar installation. The remedial investigation (RI) field activities were conducted at the Point Lay radar installation during the summer of 1993. The four sites at Point Lay were investigated because they were suspected of being contaminated with hazardous substances. RI activities were conducted using methods and procedures specified in the RI/FS Work Plan, Sampling and Analysis Plan (SAP), and Health and Safety Plan.

Karmi, S.

1996-03-04

130

Nuclear Construction Engineering Technology.  

National Technical Information Service (NTIS)

This report provides the technology which enables the engineer to make engineering, safety and cost analysis of the applicability and feasibility of using nuclear explosives in conjunction with the construction of specific civil works projects. A discussi...

B. C. Hughes

1968-01-01

131

The Estuary Book: A Guide to Promoting Understanding and Regional Management of Maine's Estuaries and Embayments.  

ERIC Educational Resources Information Center

|The objective of this document is to provide information about estuaries, the impact of uses on the environmental health of an estuary, and what communities and concerned individuals can do to manage and protect their local estuarine resources successfully. Much of the information presented here pertains to other embayments along the Maine coast…

Ruffing, Jenny

132

Estuaries.  

ERIC Educational Resources Information Center

|This publication is designed for use in standard science curricula to develop oceanologic manifestations of certain science topics. Included are teacher guides, student activities, and demonstrations designed to impart ocean understanding to high school students. When the student has completed this unit, he should be able to: (1) define an…

Awkerman, Gary L.

133

Flow Liner Slot Edge Replication Feasibility Study.  

National Technical Information Service (NTIS)

Surface replication has been proposed as a method for crack detection in space shuttle main engine flowliner slots. The results of a feasibility study show that examination of surface replicas with a scanning electron microscope can result in the detectio...

J. A. Newman S. A. Willard S. W. Smith R. S. Piascik

2006-01-01

134

Assault Boat Coxswain Trainer Feasibility Study.  

National Technical Information Service (NTIS)

An in-house study was conducted to determine the engineering feasibility of an assault boat coxswain trainer. Investigations were made to identify the training problem and possible training equipment which will simulate the various situations that a coxsw...

M. Aronson F. Chea

1967-01-01

135

Manganese and Suspended Matter in the Yaquina Estuary, Oregon.  

National Technical Information Service (NTIS)

The longitudinal distribution of total suspended matter and total, dissolved, and particulate manganese in a small coastal plain estuary is described. The distribution of manganese is a consequence of estuarine circulation; a within-estuary maximum is inv...

R. J. Callaway D. T. Specht G. R. Ditsworth

1988-01-01

136

Sault Tribe Wind Energy Feasibility Study  

SciTech Connect

The Sault Tribe conducted a feasibility study on tribal lands in the Upper Peninsula of Michigan to determine the technical and economic feasibility of both small and large-scale wind power development on tribal lands. The study included a wind resource assessment, transmission system analysis, engineering and regulatory analyzes and assessments.

Toni Osterhout; Global Energy Concepts

2005-07-31

137

Sault Tribe Wind Energy Feasibility Study  

Microsoft Academic Search

The Sault Tribe conducted a feasibility study on tribal lands in the Upper Peninsula of Michigan to determine the technical and economic feasibility of both small and large-scale wind power development on tribal lands. The study included a wind resource assessment, transmission system analysis, engineering and regulatory analyzes and assessments.

Toni Osterhout

2005-01-01

138

APPLICATION OF MIKE PACKAGE TO ASSESS HYDRAULIC REGIMES AND FLOOD MAPPING WHEN CONSTRUCTION OF THERMAL POWER AT THE MONG DUONG ESTUARY (QUANG NINH)  

Microsoft Academic Search

The article presents the results formulated the effect to hydraulic regimes and inundated areas when construction of thermal power factory at the estuary of Mong Duong river by using the package of MIKE including Mike NAM, Mike11-HD and Mike-GIS with 2 options of canal width as well its location. The simulated results show that Mike package seems feasibly to formulate

VU MINH CAT; BUI DU DUONG

2007-01-01

139

SAN FRANCISCO ESTUARY PROJECT COMPREHENSIVE CONSERVATION AND MANAGEMENT PLAN  

EPA Science Inventory

The Estuary, a significant natural resource, San Francisco Bay and the Delta combine to form the West Coast's largest estuary. The Estuary conveys the waters of the Sacramento and San Joaquin Rivers to the Pacific Ocean. It encompasses roughly 1,600 square miles, drains over 40 p...

140

Tidal asymmetry in estuaries with mixed semidiurnal\\/diurnal tides  

Microsoft Academic Search

Tidal asymmetry in estuaries with mixed, mainly semidiurnal tides arises from both the interaction of principal tides and the higher harmonics generated by distortions within the estuary. The duration asymmetry in rise and fall of water level caused by principal tides on the west coast of the continental United States is ebb-dominant, and so the tide entering estuaries is also

Nicholas J. Nidzieko

2010-01-01

141

Biological effects of anthropogenic contaminants in the San Francisco Estuary  

Microsoft Academic Search

Concentrations of many anthropogenic contaminants in the San Francisco Estuary exist at levels that have been associated with biological effects elsewhere, so there is a potential for them to cause biological effects in the Estuary. The purpose of this paper is to summarize information about biological effects on the Estuary's plankton, benthos, fish, birds, and mammals, gathered since the early

Bruce Thompson; Terry Adelsbach; Cynthia Brown; Jennifer Hunt; James Kuwabara; Jennifer Neale; Harry Ohlendorf; Steve Schwarzbach; Robert Spies; Karen Taberski

2007-01-01

142

The Estuary Guide. Level 3: High School. Draft.  

ERIC Educational Resources Information Center

Estuaries are marine systems that serve as nurseries for animals, links in the migratory pathways, and habitat for a complex community of organisms. This curriculum guide intended for use at the high school level seeks to teach what estuaries are; provide opportunities to practice decision-making that affects estuaries; and encourage students to…

Alexander, Glen; And Others

143

The Estuary Guide. Level 3: High School. Draft.  

ERIC Educational Resources Information Center

|Estuaries are marine systems that serve as nurseries for animals, links in the migratory pathways, and habitat for a complex community of organisms. This curriculum guide intended for use at the high school level seeks to teach what estuaries are; provide opportunities to practice decision-making that affects estuaries; and encourage students to…

Alexander, Glen; And Others

144

Rapid barium removal in the Delaware estuary  

SciTech Connect

Six profiles of dissolved barium covering the entire salinity range of the Delaware River and Bay estuary from March through September 1996 were collected and analyzed. The profiles are similar to one another in both shape and magnitude except for one attribute. A sudden ({le} 24 days), nearly complete (>90%) removal of dissolved Ba in midestuary occurs in mid-May followed by an 80% recovery in early June. This removal appears to be temporally and spatially coupled to the end of the spring bloom. Based on such episodic behavior, and on recent work with flocculation of diatom exudates, the authors conclude that the Ba depletion is caused by barite precipitation in the estuary during the late stages of the bloom. This would imply that lower estuary and inner coastal margin sediments associated with eutrophic estuaries receive a seasonal pulse of barite. The suddenness of this event also implies that sedimentary barite is strongly influenced by high productivity events. Comparison of the riverine Ba concentration with the effective riverine end member after desorptive barium release yields an estimated 30--40 nM Ba available from the suspended sediments as they enter the estuary. This estimate is supported by excess barium in unfiltered samples over filtered samples taken from the river and also by calculations done elsewhere.

Stecher, H.A. III [Univ. of Delaware, Lewes, DE (United States). College of Marine Studies]|[Univ. of Delaware, Newark, DE (United States). Dept. of Geology; Kogut, M.B. [Univ. of Washington, Seattle, WA (United States). School of Oceanography

1999-04-01

145

A comparative study of mercury contamination in the Tagus estuary (Portugal) and major French estuaries (Gironde, Loire, Rhône)  

NASA Astrophysics Data System (ADS)

Concentrations of mercury were determined for the waters, suspended matter and sediments of the Tagus and of major French estuaries. The Tagus estuary is one of the most contaminated by mercury derived from the outfalls of a chloralkali plant and from other industrial sources. In deposited sediments the median level, 1·0 ?g Hg g -1, is twenty times higher than the natural background and Hg contents depend on the sediment grain-size, age and the distance from waste-outfalls. Suspended matter is more regularly and highly contaminated (median value: 4·5 ?g Hg g -1). In the French estuaries Hg levels in the suspended material decrease with salinity due to dilution and/or remobilization processes. In June 1982, in the Loire estuary, high values of Hg are observed in the middle estuary and attributed to urban and industrial sources. In the Tagus estuary, the general distribution of total dissolved Hg confirms the contamination: it increases seaward from 10 ng 1 -1 in the river to 80 ng 1 -1 in the estuary outlet. The dissolved Hg is almost totally organic in the river, inorganic in the middle estuary due to inorganic Hg effluents and again organic in the lower estuary. This variation is related to the dissolved organic carbon values. The dissolved Hg levels in the Loire Estuary (5-300 ng 1 -1) are much higher than in the Gironde estuary (3-6 ng 1 -1) and of the same order as those observed in the Tagus estuary.

Figueres, G.; Martin, J. M.; Meybeck, M.; Seyler, P.

1985-02-01

146

Stratigraphic Evidence of Eutrophication in an Estuary  

NASA Astrophysics Data System (ADS)

Vertical changes in chlorophyll degradation products preserved in sediments deposited in an urban estuary show a significant increase in algal productivity with the introduction of sewage effluent into the river. By comparison, algal production during intensive agriculture of the watershed, including heavy applications of fertilizers, was less by an order of magnitude where there was no sewage discharge from a point source. Concentrations of orthophosphorus correspond with concentrations of algal cells and chlorophyll in the water column and are greater by an order of magnitude where sewage is discharged into an estuary draining an urban-agricultural watershed than where there is no sewage. The response of the estuary to short- and long-term changes in the amount of sewage discharged is reflected by similar changes in chlorophyll production. However, chlorophyll production does not correspond with increases in the amount of fertilizers used in recent years over the amount used in the middle to late nineteenth century.

Brush, Grace S.

1984-05-01

147

Geochemistry of tin in rivers and estuaries  

NASA Astrophysics Data System (ADS)

On the basis of measurements from a large number of rivers from pristine and polluted regions, we estimate the riverine fluxes of tin to the oceans to be 0.76 × 10 6molyr-1 for the dissolved fraction and 300-600 × 10 6 mol yr -1 for the paniculate fraction. The paniculate flux agrees with the flux calculated from denudation rates. Estuaries were found not to have a large effect upon the transport of tin to the oceans. Evidence for the remobilization of tin was found in an estuary that is highly polluted with tin from mining and smelting activities. Monobutyltin was found to be present in polluted estuaries and is presumed to be a degradation product of tributyltin additives to antifouling paint.

Byrd, James T.; Andreae, Meinrat O.

1986-05-01

148

National Estuary Program after four years: A report to congress  

SciTech Connect

The National Estuary Program After Four Years: A Report to Congress is a status report on the National Estuary Program (NEP) and the seventeen Management Conferences that are part of the NEP. The Report is divided into: Part I Meeting a Need: The National Estuary Program; Part II Understanding Estuaries: The Key to Better Management; Part III Managing Estuaries: The Best Methods; Part IV Assessing the NEP: What Has Been Learned; Part V Looking to the Future: Trends and Needs; and Part VI Moving Ahead: The NEP Projects.

Not Available

1992-04-01

149

ENGINEERING FEASIBILITY AND ECONOMICS OF CO2 SEQUESTRATION/USE ON AN EXISTING COAL-FIRED POWER PLANT: A LITERATURE REVIEW  

SciTech Connect

The overall objective of this study is to evaluate the technical feasibility and the economics of alternate CO{sub 2} capture and sequestration/use technologies for retrofitting an existing pulverized coal-fired power plant. To accomplish this objective three alternative CO{sub 2} capture and sequestration systems will be evaluated to identify their impact on an existing boiler, associated boiler auxiliary components, overall plant operation and performance and power plant cost, including the cost of electricity. The three retrofit technologies that will be evaluated are as follows: (1) Coal combustion in air, followed by CO{sub 2} separation from flue gas with Kerr-McGee/ABB Lummus Global's commercial MEA-based absorption/stripping process. (2) Coal combustion in an O{sub 2}/CO{sub 2} environment with CO{sub 2} recycle. (3) Coal combustion in air with oxygen removal and CO{sub 2} captured by tertiary amines In support of this objective and execution of the evaluation of the three retrofit technologies a literature survey was conducted. It is presented in an ''annotated'' form, consistent with the following five sections: (1) Coal Combustion in O{sub 2}/CO{sub 2} Media; (2) Oxygen Separation Technologies; (3) Post Combustion CO{sub 2} Separation Technologies; (4) Potential Utilization of CO{sub 2}; and (5) CO{sub 2} Sequestration. The objective of the literature search was to determine if the three retrofit technologies proposed for this project continue to be sound choices. Additionally, a review of the literature would afford the opportunity to determine if other researchers have made significant progress in developing similar process technologies and, in that context, to revisit the current state-of-the-art. Results from this literature survey are summarized in the report.

Carl R. Bozzuto; Nsakala ya Nsakala

2000-01-31

150

San Francisco Estuary: Invasive Spartina Project  

NSDL National Science Digital Library

The Invasive Spartina Project was developed by the California State Coastal Conservancy to determine the extent and address the problem of invasive Spartina in the San Francisco Estuary. This Web site describes the efforts of the Invasive Spartina Project and the risk that Spartina poses. A variety of maps and photos are used to describe the results of the 2000-2001 survey of Spartina populations within the estuary. A host of other documents regarding Spartina and this project are also available in Adobe Acrobat (.pdf) format.

2002-01-01

151

PECONIC ESTUARY: AN ASSESSMENT OF SHELLFISH RESOURCES IN THE TRIBUTARIES AND EMBAYMENTS OF THE PECONIC ESTUARY  

EPA Science Inventory

Executive Summary Historically, the Peconic Estuary's shellfish resources have supported significant fisheries for a number of species including hard clams, oysters and bay scallops. However, distribution and abundance data for the tributaries and embayments within the Peconic Es...

152

National estuary program guidance: Technical characterization in the National Estuary Program  

SciTech Connect

Estuaries are waterways, such as bays and sounds, where fresh water drained from the surrounding watershed mixes with salt water from the ocean. Section 320 of the Clean Water Act established the National Estuary Program (NEP) to identify nationally significant estuaries threatened by pollution, development, or overuse and to promote the preparation of comprehensive management plans to ensure their ecological integrity. The program's goals are protection and improvement of water quality and enhancement of living resources. To reach these goals, the Administrator of the U.S. Environmental Protection Agency (EPA) convenes management conferences for each estuary in the NEP to provide a forum for consensus building and problem solving among interested agencies and user groups.

Not Available

1994-06-01

153

The estuary part of low-inflow estuaries: stratification and residence in a Tomales Bay tributary estuary  

Microsoft Academic Search

Flow continues in Lagunitas Creek throughout the summer, delivering freshwater to the hypersaline Tomales Bay estuary. The freshwater-saltwater interface is found in the narrow estuarine channel that connects the creek and the bay, with minimal freshwater influence being found seaward of the broad shallow deltaic region at the head of the deeper sections of Tomales Bay. Observations of salinity, temperature,

R. M. Abe; J. Largier

2008-01-01

154

Control of phytoplankton biomass in estuaries: A comparative analysis of microtidal and macrotidal estuaries  

Microsoft Academic Search

Macrotidal estuaries (mean tidal range >2m) generally exhibit a tolerance to pollution with nitrogen-containing nutrients\\u000a despite high loadings originating from freshwater outflows. These systems, which are characterized by high tidal energy, generally\\u000a exhibit lower levels of chlorophylla than systems with lower tidal energy. A comparative analysis of data from 40 microtidal and macrotidal estuaries shows that\\u000a mean annual chlorophylla levels

Yves Monbet

1992-01-01

155

Influence of intermittent estuary outflow on coastal sediments of adjacent sandy beaches  

Microsoft Academic Search

Outflows from estuaries potentially contribute to the productivity of adjacent coastal waters, although most previous work has been on estuaries with considerable river discharge. We investigated the influence of estuary outflow on aspects of coastal sediments adjacent to two seasonally intermittent estuaries, the Curdies and Anglesea Rivers, in southwest Victoria, Australia. For each estuary, we measured sediment organic matter, microphytobenthic

Jessica L. McKenzie; Gerry P. Quinn; Ty G. Matthews; Jan Barton; Alecia Bellgrove

2011-01-01

156

Trace metal sources in two Malaysian estuaries  

SciTech Connect

The natural background concentrations of trace metals associated with suspended sediments in the non-urbanized upper reaches of the Kelang, Selangor, and Linggi rivers (West Malaysia) have been determined. These watersheds are underlain by weathered granite and covered, generally, by tropical jungle. The mean trace metal concentrations of the sediments in ..mu..-g/g are: Mn, 396; Zn, 92; Pb, 74; Cu, 24; Cr, 37; Ni, 21, and V, 45. These values are low compared to those reported from river sediments in North American and Europe. The spectra of trace metal abundances of the suspended sediments are very similar to the spectrum of source area granites. Thus, the granites impose a strong provenance control, in spite of intense weathering processes that have converted primary minerals to clay. Suspended sediments in the non-urbanized Selangor estuary have the same trace metal concentrations as above and exhibit no effects due to human activities. Suspended sediments in the Kelange estuary show Cu, Zn, and Pb concentrations of nearly three times the natural background levels and comparable to values reported from river sediments in North America and Europe. This estuary receives inputs from the urbanized area of Kuala Lumpur and the industrialized lower Kelang valley. Pb concentrations in the estuary are higher than for many northern hemisphere rivers. Furthermore, its concentration in the tributary sediments is higher than in the source area granites. This suggests airborne dispersal of Pb from the urban source and concentration in the suspended sediments.

Nelson, B.W.; Kahn, I.S.A.

1985-01-01

157

Restoration of the Golden Horn Estuary (Halic)  

Microsoft Academic Search

Restoration of the iconic Golden Horn Estuary in Istanbul, Turkey was a substantial political, logistical, ecological, and social challenge. Forty years of uncontrolled industrial and urban growth resulted in thick layers of anoxic sediment, toxic bacteria, strong hydrogen sulfide odor, and ecologically unlivable conditions. The major components of restoration, spanning two decades, have included (1) demolition and relocation of industries

Heather M. Coleman; Gurdal Kanat; F. Ilter Aydinol Turkdogan

2009-01-01

158

Restoration of the Golden Horn Estuary (Halic).  

PubMed

Restoration of the iconic Golden Horn Estuary in Istanbul, Turkey was a substantial political, logistical, ecological, and social challenge. Forty years of uncontrolled industrial and urban growth resulted in thick layers of anoxic sediment, toxic bacteria, strong hydrogen sulfide odor, and ecologically unlivable conditions. The major components of restoration, spanning two decades, have included (1) demolition and relocation of industries and homes along the shore, (2) creation of wastewater infrastructure, (3) removal of anoxic sludge from the estuary, (4) removal of a floating bridge that impeded circulation, and (5) creation of cultural and social facilities. Although Turkey is not known as an environmental leader in pollution control, the sum of these efforts was largely successful in revitalizing the area through dramatic water quality improvement. Consequently, the estuary is once again inhabitable for aquatic life as well as amenable to local resource users and foreign visitors, and Istanbul has regained a lost sense of cultural identity. This paper focuses on literature review and personal interviews to discuss the causes of degradation, solutions employed to rehabilitate the estuary, and subsequent physicochemical, ecological, and social changes. PMID:19781731

Coleman, Heather M; Kanat, Gurdal; Aydinol Turkdogan, F Ilter

2009-09-04

159

Reversing circulation patterns in a tropical estuary  

Microsoft Academic Search

A combination of current velocity and water density measurements was used to characterize the basic patterns of water exchange in the Gulf of Fonseca, a tropical estuary on the Pacific Ocean side of Central America. The measurements were obtained during spring and neap tides in March (dry season) and June (wet season) of 2001 and consisted of profiles of current

Arnoldo Valle-Levinson; Kathryn T. Bosley

2003-01-01

160

Estuaries and Tidal Marshes. Habitat Pac.  

ERIC Educational Resources Information Center

This educational packet consists of an overview, three lesson plans, student data sheets, and a poster. The overview examines estuaries and tidal or salt marshes by discussing the plants and animals in these habitats, marsh productivity, benefits and management of the habitats, historical aspects, and development and pollution. A glossary and list…

Fish and Wildlife Service (Dept. of Interior), Washington, DC.

161

Bacterioplankton dynamics in the Mondego estuary (Portugal)  

Microsoft Academic Search

In this work, the density of bacterioplankton and environmental parameters were monitored over a 11 month period (July 1999-June 2000), and also during one tidal cycle (15 June 2000), at two sampling stations, in the estuary of River Mondego. These data were treated by multivariate analyses methods in order to identify the key factors that control the dynamics of the

P. Bacelarnicolau; L. B. Nicolau; J. C. Marques; F. Morgado; R. Pastorinho; U. M. Azeiteiro

2003-01-01

162

Kaua'i: Streams and Estuaries.  

ERIC Educational Resources Information Center

Designed to help teachers develop students' awareness and understanding of some of Hawaii's endangered aquatic resources, this module contains activities and instructional suggestions for use with intermediate as well as high school students. The module is divided into two sections which explore the streams and estuaries of Kauai. Activities in…

Hawkins, John, Ed.; Murakami, Colleen, Ed.

163

VOLUNTEER ESTUARY MONITORING: A METHOD MANUAL  

EPA Science Inventory

Executive Summary: This manual focuses on volunteer estuary monitoring. As concern over the well-being of the environment has increased during the past couple of decades, volunteer monitoring has become an integral part of the effort to assess the health of our nation’s wat...

164

BCG Approaches for Improved Management of Estuaries  

EPA Science Inventory

Estuaries and other complex aquatic systems are exposed to a variety of stressors that act at several scales, but are managed piecemeal - - often resulting in a â??death by 1000 cutsâ? caused by cumulative impacts to these valued resources. To address this, managers need tools that...

165

Mercury pollution in the Ems estuary  

NASA Astrophysics Data System (ADS)

From approximately 1960 to 1975 the Ems estuary received several tons of mercury per year from a chlor-alkali plant, a pesticide factory and some minor sources. The discharge has been reduced drastically from 1976 onwards. In 1975 and 1976 measurements were made on the distribution of mercury in the sediment. The horizontal distribution revealed a strong local enrichment of the sediment near the point of discharge. The vertical distribution was found to be in accordance with the local deposition rates. In the water phase no significant change in mercury content from 1975 to 1978/79 could be demonstrated. In 1978/79 a difference between Ems estuary and Dutch Wadden Sea was not significant. In 1978 mercury contents of eelpout Zoarces viviparus in the Ems estuary were about twice as high as in the Wadden Sea. In the Ems estuary a decrease of these contents was found between 1974/75 and 1978. A similar decline in the Wadden Sea may be related to a decreased mercury discharge by the River Rhine.

Essink, K.

1980-03-01

166

Reversing circulation patterns in a tropical estuary  

NASA Astrophysics Data System (ADS)

A combination of current velocity and water density measurements was used to characterize the basic patterns of water exchange in the Gulf of Fonseca, a tropical estuary on the Pacific Ocean side of Central America. The measurements were obtained during spring and neap tides in March (dry season) and June (wet season) of 2001 and consisted of profiles of current velocity and density along four transects. From mid-March to mid-April a time series of hourly surface current velocity maps was also obtained with a high-frequency radar system of two antennas. The sampling transects and the radar coverage concentrated in the portion of the estuary that has open communication with the ocean. During the dry season, water exchange at the entrance to the gulf suggested an inverse estuarine circulation that was more robust, and its dynamics were closer to geostrophy during neap than during spring tides. It is likely that salinity increased toward the tributaries of the system and then decreased within those tributaries because of the persistent influence of fresh water. In contrast, during the wet season, salinity decreased into the estuary, and the circulation resembled that of a typical estuary. In this season the fortnightly modulation of exchange flows was masked by wind effects, which also played a relevant role in the dynamics. The net volume inflows measured in both seasons suggested that the residence time of the Gulf of Fonseca varies from 2 weeks to 1 month.

Valle-Levinson, Arnoldo; Bosley, Kathryn T.

2003-10-01

167

TAMPA BAY ESTUARY PROGRAM, 2004 IMPLEMENTATION REVIEW  

EPA Science Inventory

The Tampa Bay Estuary Program and its partners have made measurable progress toward implementation of the adopted CCMP goals. Progress has occurred in the following areas: bay habitats, with an increase in seagrass, estuarine habitat restoration and preservation; water and sedime...

168

DELAWARE ESTUARY PROGRAM IMPLEMENTATION STREAMLINE REVIEW, 2002  

EPA Science Inventory

The primary purpose of the Delaware Estuary Program implementation review (formerly known as the biennial review) has been to assist EPA in. making funding decisions for those NEPs that are in the post-CCMP, or implementation, phase, and to evaluate implementation progress. The i...

169

Kaua'i: Streams and Estuaries.  

ERIC Educational Resources Information Center

|Designed to help teachers develop students' awareness and understanding of some of Hawaii's endangered aquatic resources, this module contains activities and instructional suggestions for use with intermediate as well as high school students. The module is divided into two sections which explore the streams and estuaries of Kauai. Activities in…

Hawkins, John, Ed.; Murakami, Colleen, Ed.

170

Listening to Estuary English in Singapore  

ERIC Educational Resources Information Center

|In Singapore, many people are not familiar with Estuary English (EE), the variety of English becoming popular in much of southern England. In the current study, when students listened to interviews with EE speakers and were asked to transcribe orthographically what they heard, most of them had severe problems. Features of pronunciation that…

Deterding, David

2005-01-01

171

Estuaries and Tidal Marshes. Habitat Pac.  

ERIC Educational Resources Information Center

|This educational packet consists of an overview, three lesson plans, student data sheets, and a poster. The overview examines estuaries and tidal or salt marshes by discussing the plants and animals in these habitats, marsh productivity, benefits and management of the habitats, historical aspects, and development and pollution. A glossary and…

Fish and Wildlife Service (Dept. of Interior), Washington, DC.

172

Padilla Bay: The Estuary Guide. Level 2.  

ERIC Educational Resources Information Center

|Estuaries are marine systems that serve as nurseries for animals, links in the migratory pathways, and habitat for a complex community of organisms. This curriculum guide intended for use at the middle school level is designed for use with the on-site program developed by the Padilla Bay National Esturine Research Reserve (Washington). The guide…

Friesem, Judy; Lynn, Valerie, Ed.

173

THE ECOLOGICAL CONDITION OF VERACRUZ, MEXICO ESTUARIES  

EPA Science Inventory

During June and July, 2002, forty-seven stations were sampled within estuaries along the gulf coast of the state of Veracruz, MX, using a probabilistic survey design and a common set of response indicators. The objective of the study was to collect information to assess the condi...

174

INDICATORS OF ECOSYSTEM INTEGRITY FOR ESTUARIES  

EPA Science Inventory

Jordan, Stephen J. and Lisa M. Smith. In press. Indicators of Ecosystem Integrity for Estuaries. In: Proceedings of the Estuarine Indicators Workshop, 29-31 October 2003, Sanibel Island, FL. Sanibel-Captiva Conservation Foundation, Sanibel, FL. 23 p. (ERL,GB 1194). Ideal ...

175

BATHYMETRY FOR ALBEMARLE AND PAMLICO ESTUARIES, NC  

EPA Science Inventory

Bathymetry for the Albemarle and Pamlico Estuaries obtained from National Oceanographic and Atmospheric Administration-National Ocean Service (NOAA-NOS). See the metadata within the files from NOAA-NOS for more details and warnings concerning merging with US Geolgoical Survey Dig...

176

Improving lakebed sediment quality in an urban estuary, Presque Isle Bay, Lake Erie, USA  

NASA Astrophysics Data System (ADS)

Presque Isle Bay, Lake Erie, is a microtidal freshwater estuary on the North American Great Lakes. It is one of 40 remaining environmental Areas of Concern (AoCs) on the Great Lakes that have one or more water, habitat, or sediment quality impairments as defined by the International Joint Commission. In-situ natural capping using sediment from to-be-remediated watersheds and other sources is being considered as the most feasible means of remediating contaminated sediments in the estuary. A multi-decade sediment budget shows that, when localized anthropogenic effects are accounted for, the estuary net-accumulated sediment over time from three major sources: the Lake Erie littoral system (20%), streams (25%), and bank erosion and bluff recession (41%). The non-stream sources supply environmentally clean sediment from ancient coastal deposits along the shoreline, and from the modern littoral system. However, organic and metallic contaminants are supplied by streams and run-off and remain a remediation challenge. From a geological perspective, natural capping of contaminated sediment over the next several decades is a viable solution for the majority of the bay. The mechanism may not work effectively in all areas because approximately 25% of the bay floor is moderately net- erosional or accumulates sediments very slowly.

Foyle, A. M.; Norton, K. P.

2007-12-01

177

Baseline ecological risk assessment of the Calcasieu Estuary, Louisiana: Part 1. Overview and problem formulation.  

PubMed

A remedial investigation/feasibility study (RI/FS) of the Calcasieu Estuary cooperative site was initiated in 1998. This site, which is located in the southwestern portion of Louisiana in the vicinity of Lake Charles, includes the portion of the estuary from the saltwater barrier on the Calcasieu River to Moss Lake. As part of the RI/FS, a baseline ecological risk assessment (BERA) was conducted to assess the risks to aquatic organisms and aquatic-dependent wildlife exposed to environmental contaminants. The purpose of the BERA was to determine if adverse effects on ecological receptors are occurring in the estuary; to evaluate the nature, severity, and areal extent of any such effects; and to identify the substances that are causing or substantially contributing to effects on ecological receptors. This article describes the environmental setting and site history, identifies the chemicals of potential concern, presents the exposure scenarios and conceptual model for the site, and summarizes the assessment and measurement endpoints that were used in the investigation. Two additional articles in this series describe the results of an evaluation of effects-based sediment-quality guidelines as well as an assessment of risks to benthic invertebrates associated with exposure to contaminated sediment. PMID:21442250

MacDonald, Donald D; Moore, Dwayne R J; Ingersoll, Christopher G; Smorong, Dawn E; Carr, R Scott; Gouguet, Ron; Charters, David; Wilson, Duane; Harris, Tom; Rauscher, Jon; Roddy, Susan; Meyer, John

2011-03-26

178

Baseline ecological risk assessment of the Calcasieu Estuary, Louisiana: 1. Overview and problem formulation  

USGS Publications Warehouse

A remedial investigation/feasibility study (RI/FS) of the Calcasieu Estuary cooperative site was initiated in 1998. This site, which is located in the southwestern portion of Louisiana in the vicinity of Lake Charles, includes the portion of the estuary from the saltwater barrier on the Calcasieu River to Moss Lake. As part of the RI/FS, a baseline ecological risk assessment (BERA) was conducted to assess the risks to aquatic organisms and aquatic-dependent wildlife exposed to environmental contaminants. The purpose of the BERA was to determine if adverse effects on ecological receptors are occurring in the estuary; to evaluate the nature, severity, and areal extent of any such effects; and to identify the substances that are causing or substantially contributing to effects on ecological receptors. This article describes the environmental setting and site history, identifies the chemicals of potential concern, presents the exposure scenarios and conceptual model for the site, and summarizes the assessment and measurement endpoints that were used in the investigation. Two additional articles in this series describe the results of an evaluation of effects-based sediment-quality guidelines as well as an assessment of risks to benthic invertebrates associated with exposure to contaminated sediment.

MacDonald, Donald D.; Moore, Dwayne R.J.; Ingersoll, Christopher G.; Smorong, Dawn E.; Carr, R. Scott; Gouguet, Ron; Charters, David; Wilson, Duane; Harris, Tom; Rauscher, Jon; Roddy, Susan; Meyer, John

2011-01-01

179

Evaluating Cumulative Ecosystem Response to Restoration Projects in the Columbia River Estuary, Annual Report 2006  

SciTech Connect

This report is the third annual report of a six-year project to evaluate the cumulative effects of habitat restoration action in the Columbia River Estuary (CRE). The project is being conducted for the U.S. Army Corps of Engineers (Corps) by the Marine Sciences Laboratory of the Pacific Northwest National Laboratory, the Pt. Adams Biological Field Station of the National Marine Fisheries Service, and the Columbia River Estuary Study Taskforce. Measurement of the cumulative effects of ecological restoration projects in the Columbia River estuary is a formidable task because of the size and complexity of the estuarine landscape and the meta-populations of salmonids in the Columbia River basin. Despite the challenges presented by this system, developing and implementing appropriate indicators and methods to measure cumulative effects is the best way to enable estuary managers to track the overall effectiveness of investments in estuarine restoration projects. This project is developing methods to quantify the cumulative effects of multiple restoration activities in the CRE. The overall objectives of the 2006 study were to continue to develop techniques to assess cumulative effects, refine the standard monitoring protocols, and initiate development of an adaptive management system for Corps of Engineers’ habitat restoration monitoring efforts in the CRE. (The adaptive management effort will be reported at a later date.) Field studies during 2006 were conducted in tidal freshwater at Kandoll Farm on the lower Grays River and tidal brackish water at Vera Slough on Youngs Bay. Within each of area, we sampled one natural reference site and one restoration site. We addressed the overall objectives with field work in 2006 that, coupled with previous field data, had specific objectives and resulted in some important findings that are summarized here by chapter in this report. Each chapter of the report contains data on particular monitored variables for pre- and post-restoration conditions at both the Kandoll and Vera study areas.

Johnson, Gary E.; Borde, Amy B.; Dawley, Earl; Diefenderfer, Heida L.; Ebberts, Blaine D.; Putman, Douglas A.; Roegner, G. C.; Thom, Ronald M.; Vavrinec, John; Whiting, Allan H.

2007-12-06

180

A chemical survey of the Mississippi estuary  

SciTech Connect

A snap shot survey of the Mississippi estuary was made during a period of low river discharge, when the estuarine mixing zone was within the deltaic channels. Concentrations of H{sup +}, Ca{sup 2+}, inorganic phosphorus and inorganic carbon suggest that the waters of the river and the low salinity (<5%) portion of the estuary are near saturation with respect to calcite and sedimentary calcium phosphate. An input of oxidized nitrogen species and N{sub 2}O was observed in the estuary between O and 4{per thousand} salinity. The concentrations of dissolved NH{sub 4}{sup +} and O{sub 2}, over most of the estuary, appeared to be influenced by decomposition of terrestrial organic matter in bottom sediments. The estuarine bottom also appears to be a source of CH{sub 4} which has been suggested to originate from petroleum shipping and refining operations. Estuarine mixing with offshore Gulf waters was the dominant influence on distributions of dissolved species over most of the estuary (i.e., from salinities > 5%). The phytoplankton abundance (measured as chlorophyll a) increased as the depth of the mixed layer decreased in a manner consistent with the expected for a light-limited ecosystem. Fluxes of NO{sub 3}{sup {minus}} + NO{sub 2}{sup {minus}} and soluble inorganic phosphorus to the Gulf of Mexico were estimated to be 3.4 {plus minus} 0.2 {times} 10{sup 3} g N s{sup {minus}1} and 1.9 {plus minus} g P s{sup {minus}1}, respectively, at the time of this study.

Fox, L.E.; Lipschultz, R.; Kerkhof, L.; Wofsy, S.C. (Harvard Univ., Cambridge, MA (USA))

1987-03-01

181

Current Characterization at the Amazon estuary  

NASA Astrophysics Data System (ADS)

At the estuary there are several mechanisms that cause turbulence: influence of solid contours (estuary bottom and shores), speed vertical shearing (fluid inside), wind shearing stress (free surface) and surface and internal gravity waves. Turbulence intensity controls vertical distribution of estuary water mass property concentration. As flow into the estuary takes place during the transition or turbulent regimen, produced by small space and time scale movements, entrainment, turbulent scattering and advection are the processes responsible for fresh water mixing up with the sea and for local salinity variation, as well as for concentration of natural properties and man-made ones. According to this focus, we shall describe general circulation, conveyance and mixing characteristics of the Amazon low estuary waters. Amazon estuary shows unusual characteristics: it is of vast length and enormous outflow. It is extremely wide - 150 Km - and its discharge into the Atlantic amounts to 180,000 m3s-1 (Otman, 1968, Figueiredo et al, 1991), which means 18% of all water discharged by rivers into oceans; this is the largest punctual source of fresh water for oceans (Milliman and Meade, 1983). Maximum outflow is 2.5 x 105 m3s-1, and it happens at the end of May. Minimum outflow is 1.2 x 105 m3 s-1, and it takes place in November. At Amazon River, the Mixing Zone occurs where the Coastal Zone usually is. The reason for that is the extension of fresh water plume moves Northeast for over 1000 Km (Gibbs, 1970; Muller-Karger et al 1988). This is the most extensive estuarine plume ever found in the ocean. During low fluvial discharge (June-November) plume reaches 300 Km; however, on high discharge (November-May) plume reaches 500 Km. Plume already is 3 to 10 m thick and 80 to 300 Km wide (Lentz and Limeburner, 1995). From June to January plume moves towards Africa, from whence 70% of it goes east carried by North Brazil Current retroflection and 30% goes towards the Caribbean. From February to May, the plume goes northwest towards the Caribbean. As to classification according to salinity stratification, at the quadrature the Amazon estuary is considered as "Saline Wedge" type (highly stratified estuary), salinity at 120 Km way from river moth standing out, whereas at sysygy it can be classified as well mixed (Limeburner et al. 1991e 1992; Patchineelam, 2004). Fresh water is everywhere in the river area, salty or mixed water is located in the ocean. In this estuary 90 Km away from the mouth surface water salinity is less than 0.05 and bottom salinity at 14 m deep is about 19 at high water on quadrature at the end of the rainy season. This behavior produces marked difference in the vertical salinity profile, showing the current is moving in the opposite direction (river fresh water and salty water brought by the tide). In this scenario, speed shearing at the interface produces interfacial friction stress that, from the entrainment process carries portions of water from the sea to the upper part. Usually, therefore, in "saline wedge" (highly stratified estuary) type estuaries, when river discharge is more intensive than the tide wave, entrainment is the predominant mechanism; and the greater tide amplitude is, the greater will its influence be to produce turbulent scattering and mixing be. Probably, at Amazon estuary quadrature entrainment processes are predominant and are the ones responsible for increased salinity in surface layer, whereas turbulence scattering mixing is secondary to it. "Saline wedge" (highly stratified estuary) type estuaries are typical of large fluvial discharge and microtide regions. But although the Amazon estuary is a macrotide region, this stratification is due to the river's exceptional discharge. Due to the remarkable river plume discharge on the platform, the tide - a dominant in macrotide region estuarine circulation - now has a secondary role, albeit not a negligible one, with quadrature amplitudes varying from 2 m to 90 Km from the mouth. It is important to point out that tide-ind

Bezerra, M. O.

2009-04-01

182

33 CFR 165.1190 - Security Zone; San Francisco Bay, Oakland Estuary, Alameda, CA.  

Code of Federal Regulations, 2013 CFR

...Security Zone; San Francisco Bay, Oakland Estuary, Alameda, CA. 165.1190 Section...Security Zone; San Francisco Bay, Oakland Estuary, Alameda, CA. (a) Location. ...zone: All navigable waters of the Oakland Estuary, California, from the surface to...

2013-07-01

183

33 CFR 165.1190 - Security Zone; San Francisco Bay, Oakland Estuary, Alameda, CA.  

Code of Federal Regulations, 2010 CFR

...Security Zone; San Francisco Bay, Oakland Estuary, Alameda, CA. 165.1190 Section...Security Zone; San Francisco Bay, Oakland Estuary, Alameda, CA. (a) Location. ...zone: All navigable waters of the Oakland Estuary, California, from the surface to...

2010-07-01

184

Second International Symposium on the Biogeochemistry of Model Estuaries: Estuarine processes in global change. Final report  

SciTech Connect

This report summarizes estuary events discussed at the symposium on biogeochemistry. Topics include; sedimentation, salinity, inputs and outputs of the estuary, effects of global change, and the need for effective sampling and modeling of estuaries.

Windom, H.L.

1991-12-31

185

33 CFR 165.1190 - Security Zone; San Francisco Bay, Oakland Estuary, Alameda, CA.  

Code of Federal Regulations, 2010 CFR

...Security Zone; San Francisco Bay, Oakland Estuary, Alameda, CA. 165.1190 Section...Security Zone; San Francisco Bay, Oakland Estuary, Alameda, CA. (a) Location. ...zone: All navigable waters of the Oakland Estuary, California, from the surface to...

2009-07-01

186

An Ecosystem-Based Restoration Plan with Emphasis on Salmonid Habitats in the Lower Columbia River and Estuary  

SciTech Connect

The Bonneville Power Administration (BPA), in coordination with the U. S. Army Corps of Engineers (COE) and NOAA Fisheries, originated this project (BPA Project No. 2002-076; Contract No. DE-AC06-76RL01830, Release No. 652-24). Their intent was to develop a useful habitat restoration plan for the lower Columbia River and estuary to help guide restoration efforts and fulfill Reasonable and Prudent Alternative Action 159 of the 2000 National Marine Fisheries Service Biological Opinion on operation of the Federal Columbia River Power System. This document focuses on salmon habitat, although its ecosystem-based approach necessarily affects other species as well. Salmon habitat restoration is best undertaken within the context of other biota and physical processes using an ecosystem perspective. The anticipated audience for the plan includes entities responsible for, interested in, or affected by habitat restoration in the lower Columbia River and estuary. Timeframes to apply this plan extend from the immediate (2003-2004) to the near-term (2005-2006) to the long-term (2007 and beyond). We anticipate and encourage that the plan be revised as new knowledge and experience are attained. A team comprised of the Columbia River Estuary Study Taskforce (CREST), the Lower Columbia River Estuary Partnership (Estuary Partnership), and Pacific Northwest National Laboratory (PNNL) wrote this document. The BPA and the COE, as the responsible Action Agencies, provided technical oversight. The Estuary Partnership's Science Work Group, NOAA Fisheries Habitat Conservation Division, Northwest Power Planning Council (NPPC) staff, and state and tribal fisheries management agencies reviewed drafts. The Independent Scientific Advisory Board of the NPPC reviewed and commented on the 90% draft. Revisions were incorporated into the final draft document subsequently released for public review. Extensive efforts were made to ensure a sound technical and policy basis and to solicit input from all interested parties.

Johnson, Gary E.; Thom, Ronald M.; Whiting, Allan H.; Sutherland, George B.; Berquam, Taunja J.; Ebberts, Blaine; Ricci, Nicole M.; Southard, John A.; Wilcox, Jessica D.

2003-10-14

187

Geomorphologic and physical characteristics of a human impacted estuary: Quequén Grande River Estuary, Argentina  

NASA Astrophysics Data System (ADS)

Even though the Quequén Grande River Estuary has economic and strategic importance from an oceanographic point of view, it has been ignored until recently. Nevertheless, many anthropogenic modifications (i.e., dredging, jetty and harbour construction, etc.) have taken place in the last 100 years which, most of them, have resulted in significative economic expenses to the harbour and city authorities due to the lack of adequate prior studies. The purpose of this article is to provide a review of the present status of the geomorphology and main physical characteristics of the estuary and describe the effects of these man-made modifications upon the estuary. Data were gathered in several field cruises from 1994 to 2000 plus from continuous recording devices installed at or near the estuary directed to define the present geomorphologic and oceanographic conditions of the estuary and to establish a monitoring program. The ultimate goal is to provide some practical solutions in diminishing the maintenance of the harbour and to provide pollution-control devices. The estuary is classified as a microtidal, primary, coastal-plain system. It can be considered as a partly-mixed system 2 km from the mouth up to its head (15 km inland). Artificial dredging to accommodate the Quequén harbour in the last 2 km of the estuary has induced a highly stratified water column where the upper 2 3 m concentrates low salinity water and the lower layer is filled by water of the same or slightly higher salinity than the inner shelf waters. Due to the presence of a step at the head of the harbour, water circulation is very reduced and in some cases nonexistent, producing strong reductive and even anoxic conditions. The foot of the step is a sediment and organic matter trap that must be dredged periodically to insure adequate navigability.

Perillo, G. M. E.; Perez, D. E.; Piccolo, M. C.; Palma, E. D.; Cuadrado, D. G.

2005-01-01

188

Evaluation of Life History Diversity, Habitat Connectivity, and Survival Benefits Associated with Habitat Restoration Actions in the Lower Columbia River and Estuary, Annual Report 2010  

SciTech Connect

This report describes the 2010 research conducted under the U.S. Army Corps of Engineers (USACE) project EST-P-09-1, titled Evaluation of Life History Diversity, Habitat Connectivity, and Survival Benefits Associated with Habitat Restoration Actions in the Lower Columbia River and Estuary, and known as the 'Salmon Benefits' study. The primary goal of the study is to establish scientific methods to quantify habitat restoration benefits to listed salmon and trout in the lower Columbia River and estuary (LCRE) in three required areas: habitat connectivity, early life history diversity, and survival (Figure ES.1). The general study approach was to first evaluate the state of the science regarding the ability to quantify benefits to listed salmon and trout from habitat restoration actions in the LCRE in the 2009 project year, and then, if feasible, in subsequent project years to develop quantitative indices of habitat connectivity, early life history diversity, and survival. Based on the 2009 literature review, the following definitions are used in this study. Habitat connectivity is defined as a landscape descriptor concerning the ability of organisms to move among habitat patches, including the spatial arrangement of habitats (structural connectivity) and how the perception and behavior of salmon affect the potential for movement among habitats (functional connectivity). Life history is defined as the combination of traits exhibited by an organism throughout its life cycle, and for the purposes of this investigation, a life history strategy refers to the body size and temporal patterns of estuarine usage exhibited by migrating juvenile salmon. Survival is defined as the probability of fish remaining alive over a defined amount of space and/or time. The objectives of the 4-year study are as follows: (1) develop and test a quantitative index of juvenile salmon habitat connectivity in the LCRE incorporating structural, functional, and hydrologic components; (2) develop and test a quantitative index of the early life history diversity of juvenile salmon in the LCRE; (3) assess and, if feasible, develop and test a quantitative index of the survival benefits of tidal wetland habitat restoration (hydrologic reconnection) in the LCRE; and (4) synthesize the results of investigations into the indices for habitat connectivity, early life history diversity, and survival benefits.

Diefenderfer, Heida L.; Johnson, Gary E.; Sather, Nichole K.; Skalski, J. R.; Dawley, Earl M.; Coleman, Andre M.; Ostrand, Kenneth G.; Hanson, Kyle C.; Woodruff, Dana L.; Donley, Erin E.; Ke, Yinghai; Buenau, Kate E.; Bryson, Amanda J.; Townsend, Richard L.

2011-10-01

189

Iron isotope fractionation in subterranean estuaries  

NASA Astrophysics Data System (ADS)

Dissolved Fe concentrations in subterranean estuaries, like their river-seawater counterparts, are strongly controlled by non-conservative behavior during mixing of groundwater and seawater in coastal aquifers. Previous studies at a subterranean estuary of Waquoit Bay on Cape Cod, USA demonstrate extensive precipitation of groundwater-borne dissolved ferrous iron and subsequent accumulation of iron oxides onto subsurface sands. Waquoit Bay is thus an excellent natural laboratory to assess the mechanisms of Fe-isotope fractionation in redox-stratified environments and determine potential Fe-isotope signatures of groundwater sources to coastal seawater. Here, we report Fe isotope compositions of iron-coated sands and porewaters beneath the intertidal zone of Waquoit Bay. The distribution of pore water Fe shows two distinct sources of Fe: one residing in the upward rising plume of Fe-rich groundwater and the second in the salt-wedge zone of pore water. The groundwater source has high Fe(II) concentration consistent with anoxic conditions and yield ?56Fe values between 0.3 and -1.3‰. In contrast, sediment porewaters occurring in the mixing zone of the subterranean estuary have very low ?56Fe values down to -5‰. These low ?56Fe values reflect Fe-redox cycling and result from the preferential retention of heavy Fe-isotopes onto newly formed Fe-oxyhydroxides. Analysis of Fe-oxides precipitated onto subsurface sands in two cores from the subterranean estuary revealed strong ?56Fe and Fe concentration gradients over less than 2m, yielding an overall range of ?56Fe values between -2 and 1.5‰. The relationship between Fe concentration and ?56Fe of Fe-rich sands can be modeled by the progressive precipitation of Fe-oxides along fluid flow through the subterranean estuary. These results demonstrate that large-scale Fe isotope fractionation (up to 5‰) can occur in subterranean estuaries, which could lead to coastal seawater characterized by very low ?56Fe values relative to river values.

Rouxel, Olivier; Sholkovitz, Edward; Charette, Matthew; Edwards, Katrina J.

2008-07-01

190

Ceramic Automotive Stirling Engine Program.  

National Technical Information Service (NTIS)

The Ceramic Automotive Stirling Engine Program evaluated the application of advanced ceramic materials to an automotive Stirling engine. The objective of the program was to evaluate the technical feasibility of utilizing advanced ceramics to increase peak...

1986-01-01

191

Benthic primary production in the Columbia River Estuary. Final report  

SciTech Connect

The general objective of the research associated with the Benthic Primary Production Work Unit of Columbia River Estuary Development Program was to determine mechanisms that control the production dynamics and species composition of benthic plant assemblages in the Columbia River Estuary. In particular, the work was concerned with effects of selected physical variables on structural and functional attributes of micro- and macro- vegetation, and on the productivity and biomass of benthic autotrophs on the tidal flats of the estuary.

McIntire, C.D.; Amspoker, M.C.

1984-02-01

192

Biological components from the Seine estuary: first results  

Microsoft Academic Search

The Seine estuary plays an important role in the dynamics of the eastern English Channel ecosystem. Nevertheless, its biological\\u000a compartment is poorly known. This constitutes an important handicap to establish the precise state of the health of this major\\u000a European estuary. The objectives of this study were to identify the life resources of the estuary: macrobenthos, mesozooplankton,\\u000a suprabenthos, and fish

Pascal Mouny; Jean Claude Dauvin; Christophe Bessineton; Bernard Elkaim; Serge Simon

1998-01-01

193

Driving forces and management strategies for estuaries in northern China  

Microsoft Academic Search

Estuaries, which lie at the end of rivers, belong to the interlocking area between marine ecosystems and terrestrial ecosystems.\\u000a In the estuary region, there are plenty of biological resources that carry many important ecosystem services. However, severe\\u000a degradation of the estuary ecosystem in northern China has been caused by anthropogenic disturbances, including water pollution\\u000a from upstream area, change of marine

Anning Suo; Dongzhi Zhao; Fengshou Zhang; Huaru Wang; Fengqiao Liu

2010-01-01

194

Migratory Behavior and Survival of Juvenile Salmonids in the Lower Columbia River and Estuary in 2009  

SciTech Connect

The study reported herein was funded as part of the Anadromous Fish Evaluation Program, which is managed by the U.S. Army Corps of Engineers (USACE). The Anadromous Fish Evaluation Program study code is EST P 02 01: A Study of Salmonid Survival and Behavior through the Columbia River Estuary Using Acoustic Tags. The study was conducted by the Pacific Northwest National Laboratory (PNNL) and National Oceanic and Atmospheric Administration (NOAA) Fisheries for the USACE Portland District. Estimated survival of acoustic-tagged juvenile Chinook salmon and steelhead through the lower Columbia River and estuary in 2009 was lowest in the final 50 km of the estuary. Probability of survival was relatively high (>0.90) for yearling and subyearling Chinook salmon from the Bonneville Dam forebay (rkm 236) to Three-tree Point (rkm 49.6). Survival of juvenile Chinook salmon declined sharply through the lower 50 km of the estuary. Acoustic-tagged steelhead smolts did not survive as well as juvenile Chinook salmon between Bonneville Dam and the mouth of the Columbia River. Steelhead survival began to decline farther upstream (at rkm 86) relative to that of the Chinook salmon stocks. Subyearling Chinook salmon survival decreased markedly as the season progressed. It remains to be determined whether later migrating subyearling Chinook salmon are suffering increasing mortality as the season progresses or whether some portion of the apparent loss is due to fish extending their freshwater residence. This study provided the first glimpse into what promises to be a very informative way to learn more about how juvenile salmonid passage experiences through the FCRPS may influence their subsequent survival after passing Bonneville Dam. New information regarding the influence of migration pathway through the lower 50 km of the Columbia River estuary on probability of survival of juvenile salmonids, combined with increased understanding regarding the foraging distances and time periods of avian predators should prove useful in developing or assessing management actions to reduce losses of juvenile salmonid smolts that attempt to pass through the estuary on their seaward migration.

McMichael, Geoffrey A.; Harnish, Ryan A.; Bellgraph, Brian J.; Carter, Jessica A.; Ham, Kenneth D.; Titzler, P. Scott; Hughes, Michael S.

2010-08-01

195

Mercury pollution in the Ems estuary  

Microsoft Academic Search

From approximately 1960 to 1975 the Ems estuary received several tons of mercury per year from a chlor-alkali plant, a pesticide\\u000a factory and some minor sources. The discharge has been reduced drastically from 1976 onwards. In 1975 and 1976 measurements\\u000a were made on the distribution of mercury in the sediment. The horizontal distribution revealed a strong local enrichment of\\u000a the

K. Essink

1980-01-01

196

SUCCESSION OF TWO ACARTIA SPECIES IN ESTUARIES  

Microsoft Academic Search

In New England and Middle Atlantic estuaries ,&art&x cZu24si, a winter-spring copepod, and A. tonsa, a summer-fall form, alternate cycles of dominance. Succession from clnusi to tonsa during spring starts near the head of an embaymcnt and spreads seaward. Concurrent observation in Narragansett Bay, Raritan Bay, and the York River plus an additional program in two Rhode Island lagoons indicated

197

Mercury biogeochemical cycling in a stratified estuary  

Microsoft Academic Search

Total Hg in the permanently stratified Pettaquamscutt estuary was <25 pM throughout the water column, even in highly sulfidic bottom waters. Particulate Hg was typically >40% of the total Hg. Reactive Hg (Hg[sub R]) was generally <3 pM and decreased with depth, but there is Hg[sub R] even in the anoxic bottom waters. Elemental Hg (Hg[sup 0]) was highest in

R. P. Mason; W. F. Fitzgerald; J. Hurley; A. K. Jr. Hanson; P. L. Donaghay; J. M. Sieburth

1993-01-01

198

The Dynamics of a Partially Mixed Estuary  

Microsoft Academic Search

ABSTRACT Measurements of velocity, density, and pressure gradient in the lower Hudson River estuary were used to quantify the dominant,terms in the momentum,equation and to characterize their variations at tidal and spring? neap timescales. The vertical momentum,flux (assumed to be due mainly to turbulent shear stress) was estimated indirectly, based on the residual from the acceleration and pressure gradient terms.

W. Rockwell Geyer; John H. Trowbridge; Melissa M. Bowen

2000-01-01

199

Nutrient elements in large Chinese estuaries  

Microsoft Academic Search

Based on comprehensive observations since 1983, this study summarizes major features of nutrient elements (nitrogen, phosphorus and silicon) in large Chinese river\\/estuary systems. Elevated nutrient element levels were observed in Chinese rivers, when compared to large and less disturbed aquatic systems (e.g. the Amazon, Zaire and Orinoco). Data from this study are similar to those obtained from the polluted and\\/or

Jing Zhang

1996-01-01

200

Geothermal feasibility study for Malting Investments Inc  

SciTech Connect

The engineering feasibility of using geothermal heat in the kilning, germination, and steep water cooling processes for a malting facility is determined. The study is based upon a malting facility with an annual capacity of malting three million bushels of clean graded barley per year or 8220 bushels per day. Capital cost figures used in the feasibility study are budget prices for the basic equipment only, they do not include any other costs such as installation, instrumentation or design and engineering costs. Utility prices are based upon $0.03 per kilowatt hour and $0.4548 per therm for natural gas.

Not Available

1981-10-01

201

Mined salt storage feasibility: Engineering study report  

SciTech Connect

This study addresses a method of eliminating the surface storage of mined salt at the Deaf Smith repository site. It provides rough estimates of the logistics and costs of transporting 3.7 million tons of salt from the repository to the salt disposal site near Carlsbad, New Mexico and returning it to the repository for decommissioning backfill. The study assumes that a railcar/truck system will be installed and that the excavated salt will be transported from the repository to an existing potash mine located near Carlsbad, New Mexico approximately 300 miles from the repository. The 3.7 million tons of salt required for repository decommissioning backfill can be stored in the potash mines along with the excess salt, with no additional capital costs required for either a railcar or a truck transportation system. The capital cost for facilities to reclaim the 3.7 million tons of salt from the potash mine is estimated to be $4,400,000 with either a rail or truck transportation system. Segregating the 3.7 million tons of backfill salt in a surface storage area at the potash mine requires a capital cost of $13,900,000 with a rail system or $11,400,000 with a truck system. Transportation costs are estimated at $0.08/ton-mile for rail and $0.13/ton-mile for truck. 2 figs., 5 tabs.

Not Available

1987-07-01

202

Links between saltwater intrusion and subtidal circulation in the Changjiang Estuary: A model-guided study  

NASA Astrophysics Data System (ADS)

In this paper we discuss the links between saltwater intrusion and subtidal circulation in the Changjiang Estuary based on a 3D numerical model. We restricted our study mainly to the three major outlets of the estuary: the South Passage, the North Passage, and the North Channel. Subtidal transport is landward in the South Passage and NNW- or NW-ward on the shoals, whereas it is mainly seaward in the North Passage and North Channel. Such a residual characteristic is caused by the interaction between tide and shallow water depth. Decomposing analysis indicated that Stokes transport is the major mechanism causing this particular residual transport pattern. Under its influence, the South Passage is the most saline outlet and the North Channel is the major route discharging the Changjiang runoff. Results of a tracer experiment indicated that active water mass exchange occurs from the South Passage to the North Passage and finally to the North Channel. Thus, the salinity in each outlet is determined not only by the tidal-averaged diversion ratio around the bifurcation of the South and North Channels but also by the subtidal circulation in the waterways and on the shoals. The northerly wind produces a horizontal circulation around the river mouth, which flows into the estuary in the North Channel and out of the estuary in the South Channel and South Passage. This circulation increases the salinity in the North Channel and decreases it in the South Passage. Recent engineering projects have intensified the landward residual in the South Passage, thereby increasing the salinity in the South Passage and decreasing the salinity in the North Channel.

Wu, Hui; Zhu, Jianrong; Ho Choi, Byung

2010-10-01

203

Ecological feasibility studies in restoration decision making.  

PubMed

The restoration of degraded systems is essential for maintaining the provision of valuable ecosystem services, including the maintenance of aesthetic values. However, restoration projects often fail to reach desired goals for a variety of ecologic, financial, and social reasons. Feasibility studies that evaluate whether a restoration effort should even be attempted can enhance restoration success by highlighting potential pitfalls and gaps in knowledge before the design phase of a restoration. Feasibility studies also can bring stakeholders together before a restoration project is designed to discuss potential disagreements. For these reasons, a feasibility study was conducted to evaluate the efficacy of restoring a tidal freshwater marsh in the Potomac River near Alexandria, Virginia. The study focused on science rather than engineering questions, and thus differed in approach from other feasibility studies that are mostly engineering driven. The authors report the framework they used to conduct a feasibility study to inform other potential restoration projects with similar goals. The seven steps of the framework encompass (1) initiation of a feasibility study, (2) compilation of existing data, (3) collection of current site information, (4) examination of case studies, (5) synthesis of information in a handbook, (6) meeting with selected stakeholders, and (7) evaluation of meeting outcomes. By conducting a feasibility study using the seven-step framework, the authors set the stage for conducting future compliance studies and enhancing the chance of a successful restoration. PMID:17453281

Hopfensperger, Kristine N; Engelhardt, Katharina A M; Seagle, Steven W

2007-04-19

204

Ecological Feasibility Studies in Restoration Decision Making  

NASA Astrophysics Data System (ADS)

The restoration of degraded systems is essential for maintaining the provision of valuable ecosystem services, including the maintenance of aesthetic values. However, restoration projects often fail to reach desired goals for a variety of ecologic, financial, and social reasons. Feasibility studies that evaluate whether a restoration effort should even be attempted can enhance restoration success by highlighting potential pitfalls and gaps in knowledge before the design phase of a restoration. Feasibility studies also can bring stakeholders together before a restoration project is designed to discuss potential disagreements. For these reasons, a feasibility study was conducted to evaluate the efficacy of restoring a tidal freshwater marsh in the Potomac River near Alexandria, Virginia. The study focused on science rather than engineering questions, and thus differed in approach from other feasibility studies that are mostly engineering driven. The authors report the framework they used to conduct a feasibility study to inform other potential restoration projects with similar goals. The seven steps of the framework encompass (1) initiation of a feasibility study, (2) compilation of existing data, (3) collection of current site information, (4) examination of case studies, (5) synthesis of information in a handbook, (6) meeting with selected stakeholders, and (7) evaluation of meeting outcomes. By conducting a feasibility study using the seven-step framework, the authors set the stage for conducting future compliance studies and enhancing the chance of a successful restoration.

Hopfensperger, Kristine N.; Engelhardt, Katharina A. M.; Seagle, Steven W.

2007-06-01

205

Role and value of nitrogen regulation provided by oysters (Crassostrea virginica) in the Mission-Aransas Estuary, Texas, USA.  

PubMed

Suspension-feeding activities of oysters impart a potentially significant benefit to estuarine ecosystems via reduction of water column nutrients, plankton and seston biomass, and primary productivity which can have a significant impact on human well-being. This study considered nitrogen regulation by eastern oysters Crassostrea virginica in the Mission-Aransas Estuary, Texas, USA, as a function of denitrification, burial, and physical transport from the system via harvest. Oyster reefs were estimated to remove 502.5 kg N km(-2) through denitrification of biodeposits and 251.3 kg N km(-2) in burial of biodeposits to sediments. Nitrogen is also physically transported out of the estuary via harvest of oysters. Commercial harvest of oysters in the Mission-Aransas Estuary can remove approximately 21,665 kg N per year via physical transport from the system. We developed a transferable method to value the service of nitrogen regulation by oysters, where the potential cost equivalent value of nitrogen regulation is quantified via cost estimates for a constructed biological nutrient removal (BNR) supplement to a wastewater treatment plant. The potential annual engineered cost equivalent of the service of nitrogen regulation and removal provided by reefs in the Mission-Aransas Estuary is $293,993 yr(-1). Monetizing ecosystem services can help increase awareness at the stakeholder level of the importance of oysters beyond commercial fishery values alone. PMID:23762341

Beseres Pollack, Jennifer; Yoskowitz, David; Kim, Hae-Cheol; Montagna, Paul A

2013-06-06

206

Lasers for engine ignition  

NASA Astrophysics Data System (ADS)

The pollutant emissions and high-energy consumption of combustion engines using conventional spark plugs have long been serious environmental problems. Now, it has been demonstrated that lasers can provide a feasible green alternative. Duncan Graham-Rowe reports.

Graham-Rowe, Duncan; Won, Rachel

2008-09-01

207

Ecological Engineering Practices for the Reduction of Excess Nitrogen in Human-Influenced Landscapes: A Guide for Watershed Managers  

EPA Science Inventory

Excess nitrogen (N) in freshwater systems, estuaries, and coastal areas has well-documented deleterious effects on ecosystems. Ecological engineering practices (EEPs) may be effective at decreasing nonpoint source N leaching to surface and groundwater. However, few studies have s...

208

WATER QUALITY MODELING IN THE RIO CHONE ESTUARY  

EPA Science Inventory

Water quality in the Rio Chone Estuary, a seasonally inverse, tropical estuary, in Ecuador was characterized by modeling the distribution of biochemical oxygen demand (BOD) and dissolved inorganic nitrogen (DIN) within the water column. These two variables are modeled using modif...

209

YAQUINA BAY AND BEYOND: WHAT SHAPE ARE OUR ESTUARIES IN?  

EPA Science Inventory

The great natural beauty of Oregon's estuaries gives an impression of systems that are far less altered than those in other areas of the US. However, over the years, Yaquina Bay and other western estuaries have been variously affected by habitat loss and alteration, over harvest...

210

LOWER COLUMBIA RIVER ESTUARY PROGRAM COMPREHENSIVE CONSERVATION AND MANAGEMENT PLAN  

EPA Science Inventory

An estuary is the area where the fresh water of a river meets the salt water of an ocean. In the Columbia River system, this occurs in the lower 46 river miles. In an estuary, the river has a direct, natural connection with the open sea. This transition from fresh to salt water c...

211

The ecology of Tijuana Estuary, California: An estuarine profile  

Microsoft Academic Search

This is the first attempt to synthesize and interpret a rapidly growing data base on the estuary's diverse biota - its vegetation, algae, birds, fishes, and invertebrates. Because so many changes have occurred in response to recent catastrophic events, we describe how each aspect of the estuary appeared before 1980 and how it has responded to several perturbations. The experimental

J. B. Zedler; C. S. Nordby

1986-01-01

212

Behavior of metals in the Amur River estuary  

Microsoft Academic Search

Biogeochemical processes in estuaries determine to a significant extent the further life of chemical compounds, including metals transported by rivers. Therefore, the characteristics of the behavior of metals in waters with intermediate salinity at the river?sea interface have both scientific and practical significance [1?5]. In terms of estimation of the concentrations of dissolved metals, the estuary of the Amur River,

V. M. Shul’kin

2006-01-01

213

Dissolved Oxygen Conditions in Northern Gulf of Mexico Estuaries  

Microsoft Academic Search

Because deficient dissolved oxygen (DO) levels may have severe detrimental effects on estuarine and marine life, DO has been widely used as an indicator of ecological conditions by environmental monitoring programs. The U.S. EPA's Environmental Monitoring and Assessment Program for Estuaries (EMAP-E) monitored DO conditions in the estuaries of the Gulf of Mexico from 1991 to 1994. DO was measured

Virginia D. Engle; J. Kevin Summers; John M. Macauley

1999-01-01

214

LIMNETIC LARVAL FISH OF THE MAUMEE AND SANDUSKY RIVER ESTUARIES  

EPA Science Inventory

A total of 17 taxa were collected in the Maumee River estuary during sampling periods in 1975, 1976, and 1977. A total of 11 taxa were collected from the Sandusky River estuary in 1976. Gizzard shad/alewife, Dorosoma cepedianum/Alosa pseudoharengus, white bass/white perch, Morone...

215

Dissolved oxygen in lower Hudson Estuary: 1978--93  

Microsoft Academic Search

During summer months, dissolved oxygen (DO) concentrations in the lower Hudson estuary were usually lower than atmospheric equilibrium values. Distributions of DO along the axis of the estuary can be described by three general characteristics. Firstly, surface and bottom values lie on a single trend when plotted against salinity. Secondly, maximum DO concentrations were observed 50--75 km upstream of Manhattan

Jordan F. Clark; H. James Simpson; Richard F. Bopp; Bruce L. Deck

1995-01-01

216

Contrasting Behavior of Osmium in the Godavari River Estuary, India  

Microsoft Academic Search

We report the Os concentrations and isotopic compositions of surface samples collected along salinity gradients from two main channels within the Godavari River Estuary. Estuaries are potential a site for biogeochemical reactions affecting the flux of elements from rivers into the oceans. Given that the seawater Os isotopic composition reflects a balance between the radiogenic continental input and unradiogenic mantle

M. Sharma; K. Balakrishna; A. Hofmann; R. Shankar

2001-01-01

217

The Hydrography of the Chupa Estuary, White Sea, Russia  

Microsoft Academic Search

This study was undertaken to determine the fate and fluxes of materials from Arctic estuaries to the coastal zone. The paper is the first of a series addressing questions relating to the physics and chemistry of the region. Three seasonal cruises were undertaken in the Chupa Estuary, White Sea, Russia; in summer (July 1994), autumn (September, 1995) and spring (May\\/June

R. J. M. Howland; A. N. Pantiulin; G. E. Millward; R. Prego

1999-01-01

218

PECONIC ESTUARY PROGRAM COMPREHENSIVE CONSERVATION AND MANAGEMENT PLAN  

EPA Science Inventory

The Peconic Estuary, situated between the North and South Forks of eastern Long Island, New York, consists of more than 100 distinct bays, harbors, embayments, and tributaries. The area surrounding the Peconic Estuary's watershed is rich in rolling farmland, scenic beaches and cr...

219

Real time simulation of nitrogen cycle in an estuary  

Microsoft Academic Search

A water quality model containing seven nitrogen storage variables appropriate to an aerobic, nitrogen limited, aquatic ecosystem is described. An idealized estuary is used to demonstrate coupling between hydrodynamic transport, mixing, and biochemical transformations. Nutrient concentrations are highly sensitive to the representation of real time (intratidal cycle) transport. Application of the model to the Potomac estuary illustrates the large temporal

T. O. Najarian; D. R. F. Harleman

1977-01-01

220

The occurrence of selected human pharmaceutical compounds in UK estuaries  

Microsoft Academic Search

This report describes a scoping study conducted in order to establish whether pharmaceutical compounds may be present in UK estuaries. Surface water samples collected from five UK estuaries were analysed for the presence of 14 pharmaceutical compounds selected from the priority lists of the UK Environment Agency and the Oslo and Paris Commission (OSPAR). The pharmaceutical compounds\\/metabolites clofibric acid, clotrimazole,

Kevin V. Thomas; Martin J. Hilton

2004-01-01

221

INDEX OF ESTUARINE BENTHIC INTEGRITY FOR GULF OF MEXICO ESTUARIES  

EPA Science Inventory

A benthic index for northern Gulf of Mexico estuaries has been developed and successfully validated by the Environmental Monitoring and Assessment Program for Estuaries (EMAP-E) in the Louisianian Province. The benthic index is a useful indicator of estuarine condition that provi...

222

The Submersed Macrophytes of the Pamlico River Estuary, North Carolina.  

National Technical Information Service (NTIS)

The ecology of the submersed aquatic macrophytes (including filamentous algae) of the Pamlico River, NC estuary was studied from the summer of 1973 through the summer of 1975. Rooted macrophytes were not found in the lower half of the estuary proper. The ...

G. J. Davis M. M. Brinson

1976-01-01

223

Three dimensional water quality modeling of a shallow subtropical estuary.  

PubMed

Knowledge of estuarine hydrodynamics and water quality comes mostly from studies of large estuarine systems. The processes affecting algae, nutrients, and dissolved oxygen (DO) in small and shallow subtropical estuaries are relatively less studied. This paper documents the development, calibration, and verification of a three dimensional (3D) water quality model for the St. Lucie Estuary (SLE), a small and shallow estuary located on the east coast of south Florida. The water quality model is calibrated and verified using two years of measured data. Statistical analyses indicate that the model is capable of reproducing key water quality characteristics of the estuary within an acceptable range of accuracy. The calibrated model is further applied to study hydrodynamic and eutrophication processes in the estuary. Modeling results reveal that high algae concentrations in the estuary are likely caused by excessive nutrient and algae supplies in freshwater inflows. While algal blooms may lead to reduced DO concentrations near the bottom of the waterbody, this study indicates that stratification and circulation induced by freshwater inflows may also contribute significantly to bottom water hypoxia in the estuary. It is also found that high freshwater inflows from one of the tributaries can change the circulation pattern and nutrient loading, thereby impacting water quality conditions of the entire estuary. Restoration plans for the SLE ecosystem need to consider both a reduction of nutrient loading and regulation of the freshwater discharge pattern. PMID:23122270

Wan, Yongshan; Ji, Zhen-Gang; Shen, Jian; Hu, Guangdou; Sun, Detong

2012-10-09

224

The behavior of trace metals in the Geum Estuary, Korea  

SciTech Connect

The distributions of trace metals in the Geum Estuary of western Korea were studied with regard to changes in other estuarine chemical parameters. Dissolved oxygen, pH, and alkalinity increased with increasing salinity. Dissolved aluminum concentrations increased at low salinities and were perhaps influenced by the solubility of particulate aluminosilicate phases. Iron, manganese, cobalt, and zinc are removed from solution in the low salinity end of the estuary. Cobalt and nickel have mid-estuary concentration maxima that may be due to an anthropogenic source. Cadmium, copper, lead, and zinc concentrations also increased in the estuary, possibly as th result of remobilization in the sediments. Cadmium increases are also linked to remineralization from tidal flat sediments in the outer estuary. The source of an increase in dissolved lead at low salinity is unclear, but may be due to release from particles.

Byrd, J.T.; Smith, R.G.; Windom, H.L. (Skidaway Inst. of Oceanography, Savannah, GA (United States)); Lee, Kwang, W. (Hanyang Univ. Ansan, Kyunggi (Korea)); Lee, Dong, S. (Korea Ocean Research and Development Inst., Ansan, Kyunggi (Korea))

1991-05-01

225

Distribution of phytoplankton pigments in nine European estuaries and implications for an estuarine typology  

Microsoft Academic Search

Phytoplankton pigments were studied by Liquid Chromatography (HPLC) in nine West European estuaries. Three estuaries, i.e. the Rhine, Scheldt and the Gironde were sampled four times to cover the different seasons, whereas the other six estuaries were sampled once. Pigment distributions in estuaries reflect both riverine inputs as well as autochthonous blooms. Fucoxanthin was the most common accessory photosynthetic pigment

EMMANUELLE LEMAIRE; GWENAËL ABRIL; RUTGER DE WIT; HENRI ETCHEBER

2002-01-01

226

Characterizing the san Francisco estuary: A case study of science management in the national estuary program  

Microsoft Academic Search

The San Francisco Estuary Project sought to “characterize”; environmental conditions in the San Francisco Bay and Sacramento?San Joaquin Delta. This task involved systematic description and analysis of conditions, to provide the scientific basis for policy reform. The focus of this paper is on activities of environmental scientists who participated on the project's Technical Advisory Committee (TAC), and their involvement on

William S. Tuohy

1993-01-01

227

Feeding preferences of estuarine mysids Neomysis integer and Rhopalophthalmus tartessicus in a temperate estuary (Guadalquivir Estuary, SW Spain)  

Microsoft Academic Search

Mysid shrimps are an important component of estuarine food webs because they play a key role in energy transfer as intermediate prey. We investigated the seasonal, tidal and depth specific variation in the diet of the estuarine mysids Neomysis integer and Rhopalophthalmus tartessicus and explored its implications for the planktonic community structure of a temperate estuary (Guadalquivir Estuary, SW Spain).

César Vilas; Pilar Drake; Nancy Fockedey

2008-01-01

228

SENSITIVITY OF NITROGEN CONCENTRATIONS IN ESTUARIES TO LOADING AND WATER RESIDENCE TIME: APPLICATION TO THE POTOMAC ESTUARY  

EPA Science Inventory

We use a simple nitrogen budget model to analyze concentrations of total nitrogen (TN) in estuaries for which both nitrogen inputs and water residence time are correlated with freshwater inflow rates. While the nitrogen concentration of an estuary varies linearly with TN loading ...

229

Near coastal program plan for 1991: Estuaries  

SciTech Connect

Environmental regulatory programs in the United States have been estimated to cost more than $70 billion annually. The Environmental Monitoring and Assessment Program (EMAP) is a nationwide initiative being implemented by EPA's Office of Research and Development (ORD). It was developed in response to the demand for information on the condition of the nation's ecological resources. The goal of EMAP is to assess and document the status and trends in the condition of the nation's forests, wetlands, estuaries, coastal waters, lakes, rivers, and streams, Great Lakes, agricultural lands, and arid lands on an integrated and continuing basis.

Not Available

1990-11-01

230

Change in Land Cover along the Lower Columbia River Estuary as Determined from Landsat Thematic Mapper (TM) Imagery, Technical Report 2003.  

SciTech Connect

The Lower Columbia River Estuary Management Plan (Jerrick, 1991) recognizes the positive relationship between the conservation of fish and wildlife habitat, and sustaining their populations. An important component of fish and wildlife conservation and management is the identification of habitats, trends in habitat change, and delineation of habitat for preservation, restoration or enhancement. Alterations to the environment, such as hydropower generation, dredging, forestry, agriculture, channel alteration, diking, bank stabilization and floodplain development, have dramatically altered both the type and distribution of habitats along the Columbia River Estuary (CRE) and its floodplain. Along the Columbia River, tidally influenced habitats occur from the river mouth to the Bonneville Dam, a distance of 230 km. If we are to effectively manage the natural resources of the Columbia River ecosystem, there is a need to understand how habitats have changed because fish and wildlife populations are known to respond to changes in habitat quality and distribution. The goal of this study was to measure the amount and type of change of CRE land cover from 1992 to 2000. We performed a change analysis on two spatial data sets describing land cover along the lower portion of the estuary (Fig. 1). The 1992 data set was created by the NOAA Coastal Remote Sensing, Coastal Change Analysis Program (C-CAP) in cooperation with Columbia River Estuary Study Task Force (CREST), the National Marine Fisheries Service (NMFS) Point Adams Field Station, and State of Washington Department of Natural Resources (DNR). The 2000 data set was produced by Earth Design Consultants, Inc. (EDC) and the Wetland Ecosystem Team (WET: University of Washington) as part of a larger Lower Columbia River Estuary Partnership (Estuary Partnership) habitat mapping study. Although the image classification methodologies used to create the data sets differed, both data sets were produced by classifying Landsat Thematic Mapper (TM) satellite imagery, making it feasible to assess land cover changes between 1992 and 2000.

Garono, Ralph; Anderson, Becci; Robinson, Rob

2003-10-01

231

Feasibility Study for Dyke Marsh Demonstration Area, Potomac River, Virginia.  

National Technical Information Service (NTIS)

Results of an investigation conducted to determine the engineering feasibility of using dredged material to expand an existing marshland area are presented. Dredged material obtained from maintenance dredging operations was found suitable for use as marsh...

M. R. Palermo T. W. Zeigler

1976-01-01

232

Feasibility study for a manufacturing technology deployment center.  

National Technical Information Service (NTIS)

The Automation & Robotics Research Institute (ARRI) and the Texas Engineering Extension Service (TEEX) were funded by the U.S. Department of Energy to determine the feasibility of a regional industrial technology institute to be located at the Superconduc...

1994-01-01

233

Summary Report: Economic Feasibility Studies of Alcohol Fuel Production Processes.  

National Technical Information Service (NTIS)

In 1983 SERI awarded six subcontracts to four engineering firms to conduct technical and economic feasibility studies of processes to convert lignocellulosic feedstocks into premium fuels (methanol and ethanol). In this report general conclusions are draw...

J. D. Wright T. Milne M. E. Karpuk S. Isaacs W. Hoagland

1986-01-01

234

Nitinol engine development  

Microsoft Academic Search

The objective of this project is to determine the feasibility of applying the shape-memory effect in certain intermetallic compounds (particularly ''55 Nitinol'') to the conversion of low temperature heat energy to mechanical work by means of solid state heat engines. A primary milestone is the development of a prototype Nitinol engine on a scale suitable for powering a moderate-size residential

M. Wahlig; R. Banks; R. Kopa; H. Mohamed

1978-01-01

235

International biomedical engineering exchanges  

Microsoft Academic Search

This is a pilot study of the feasibility of having biomedical engineers exchange jobs in other countries for a period of time. The exchange is a way of learning what our fellow biomedical engineers do. An exchange is the best way to exchange information since the exchangee actually works in the other person's job whereas at a conference there is

S. Somerwil; T. Easty

1995-01-01

236

Dissolved vanadium in rivers and estuaries  

NASA Astrophysics Data System (ADS)

New measurements of dissolved vanadium in a variety of rivers and estuaries are presented here. The data indicate that the average concentration of dissolved vanadium in major rivers entering the ocean is ˜ 15 nmol/kg. Weathering rate and type of source rock, rather than solution chemistry or anthropogenic influences, appear to be the important factors in determining fluvial dissolved vanadium concentrations. Laboratory experiments suggest that in oxic waters vanadium is found predominantly in its most oxidized, anionic form (V(V)). Complexation with organic matter and formation of large colloidal species appear to be unimportant. Adsorption also appears to be a less important influence for vanadium than for some other trace elements such as zinc. In estuaries, vanadium behaves as a bioactive element, showing a close correspondence with the distribution of phosphate. The extent of estuarine vanadium removal is presently uncertain but may be low due to rapid remineralization of this element. Based on the river flux, the oceanic residence time for dissolved vanadium is estimated to be 100,000 years.

Shiller, Alan M.; Boyle, Edward A.

1987-12-01

237

Influence of intermittent estuary outflow on coastal sediments of adjacent sandy beaches  

NASA Astrophysics Data System (ADS)

Outflows from estuaries potentially contribute to the productivity of adjacent coastal waters, although most previous work has been on estuaries with considerable river discharge. We investigated the influence of estuary outflow on aspects of coastal sediments adjacent to two seasonally intermittent estuaries, the Curdies and Anglesea Rivers, in southwest Victoria, Australia. For each estuary, we measured sediment organic matter, microphytobenthic chlorophyll a and microbial utilization of carbon sources at three locations associated with each estuary: (1) inside estuary mouth, (2) estuary swash and (3) control swash (an open beach distant from any estuarine influences). Sampling occurred one week before and at one and nine weeks after both an artificial mouth opening and a separate natural flood at both estuaries. Significant temporal changes were detected for all three variables at the estuary mouth and estuary swash but the direction of change was inconsistent across the two estuaries and between the artificial mouth opening and natural flood. Organic matter in both estuaries showed no difference after the artificial mouth openings. Only Anglesea showed an increase in organic matter in the estuary mouth and estuary swash after the floods. Microphytobenthic chlorophyll a concentrations were highest when the estuary mouths were closed. Concentrations decreased at all locations at Curdies after the mouth was artificially opened. The estuary mouth at Anglesea sustained high chlorophyll concentrations and the estuary swash increased one week post artificial opening. The flood event resulted in an increase in chlorophyll a at the estuary mouth and swash at both estuaries, one week post flood. At Curdies, the microbial utilization of different carbon sources changed after both mouth events; estuary mouth and estuary swash showed similar patterns at one and nine weeks post opening. At Anglesea, the bacteria utilized different carbon sources between locations and the only significant interaction between location and time was post flood with change in carbon sources utilized by bacteria in the estuary mouth and estuary swash for one and nine weeks post flood. The southern coastline of Australia is characterized by estuaries with small catchments. This study highlights the spatial and temporal variability in the effects of the output of relatively small, intermittent estuaries on coastal sediment of adjacent beaches, particularly during prolonged periods of drought.

McKenzie, Jessica L.; Quinn, Gerry P.; Matthews, Ty G.; Barton, Jan; Bellgrove, Alecia

2011-03-01

238

Ceramic automotive Stirling engine program  

NASA Astrophysics Data System (ADS)

The Ceramic Automotive Stirling Engine Program evaluated the application of advanced ceramic materials to an automotive Stirling engine. The objective of the program was to evaluate the technical feasibility of utilizing advanced ceramics to increase peak engine operating temperature, and to evaluate the performance benefits of such an increase. Manufacturing cost estimates were also developed for various ceramic engine components and compared with conventional metallic engine component costs.

1986-08-01

239

Ceramic Automotive Stirling Engine Program  

SciTech Connect

The Ceramic Automotive Stirling Engine Program evaluated the application of advanced ceramic materials to an automotive Stirling engine. The objective of the program was to evaluate the technical feasibility of utilizing advanced ceramics to increase peak engine operating temperature, and to evaluate the performance benefits of such an increase. Manufacturing cost estimates were also developed for various ceramic engine components and compared with conventional metallic engine component costs.

Not Available

1986-08-01

240

Resolving conflict and building cooperation in the National Estuary program.  

PubMed

Since its beginning in 1987, researchers and policymakers have touted the US Environmental Protection Agency National Estuary program (NEP) as one of the leading examples of collaborative institutions designed to resolve conflict and build cooperation at the watershed level. Using the NEP as an example, I summarize the advantages and disadvantages of collaborative institutions. Using data gathered from focused surveys of policy elites in 22 estuaries, I estimate statistical models that show the NEP does a better job of resolving conflict and building project-level cooperation than similar estuaries without the NEP. I also describe the activities of the NEP mentioned by respondents as contributing to this outcome. PMID:14727073

Lubell, Mark

2004-05-01

241

Use of the USEPA Estuary Nitrogen Model to Estimate Concentrations of Total Nitrogen in Estuaries Using Loads Calculated by Watershed Models and Monitoring Data  

EPA Science Inventory

We use USEPAâ??s Estuary Nitrogen Model (ENM) to calculate annual average concentrations of total nitrogen (TN) in ten estuaries or sub-estuaries along the Atlantic coast from New Hampshire to Florida. These include a variety of systems, ranging from strongly-flushed bays to weakly...

242

Fusion Engineering Device Design Description.  

National Technical Information Service (NTIS)

The US Magnetic Fusion Engineering Act of 1980 calls for the operation of a Fusion Engineering Device (FED) by 1990. It is the intent of the Act that the FED, in combination with other testing facilities, will establish the engineering feasibility of magn...

C. A. Flanagan D. Steiner G. E. Smith

1981-01-01

243

The Salinity Gradient and Vegetation in the Saugatucket River Estuary.  

National Technical Information Service (NTIS)

The Saugatucket River in South Kingstown, RI, discharges freshwater into Point Judith (Salt) Pond, diluting the seawater along the estuary. To locate the region of greatest salinity change in the Saugatucket River-Point Judith Pond system, 20 stations wer...

E. M. Smith R. D. Wood

1973-01-01

244

CASCO BAY ESTUARY PROJECT TRIENNIAL IMPLEMENTATION REVIEW MARCH, 2004  

EPA Science Inventory

The Casco Bay Estuary Project has seven primary goals/priorities which include: minimize pollutant loading from stormwater; open and protect shellfish beds; protect and restore habitat; reduce toxic pollution; promote responsible stewardship; sustain and promote the continued eff...

245

Columbia River Estuary Study Taskforce (CREST) Project Completion Report.  

National Technical Information Service (NTIS)

The following is a list of major activities for the period of July 1, 1985, through June 30, 1985: Dredged Material Disposal at Area D, First Quarter through Fourth Quarter Activities; Coastal Barrier Designations; Dredging, Columbia River Estuary; Dredge...

1985-01-01

246

Evaluating Causes of Ecological Impairments in the Estuaries of Ukraine  

EPA Science Inventory

Ukrainian estuaries have not undergone a systematic evaluation of the causes of ecological impairments caused by anthropogenic contamination. The objective of this evaluation is to use recently developed diagnostic tools to determine the causes of benthic ecological impairments. ...

247

MODIS water quality algorithms for northwest Florida estuaries  

EPA Science Inventory

Synoptic and frequent monitoring of water quality parameters from satellite is useful for determining the health of aquatic ecosystems and development of effective management strategies. Northwest Florida estuaries are classified as optically-complex, or waters influenced by chlo...

248

SPATIAL DISTRIBUTIONS OF BURROWING SHRIMP POPULATIONS IN TWO OREGON ESTUARIES  

EPA Science Inventory

Thalassinid burrowing shrimp (Neotrypaea californiensis and Upogebia pugettensis) inhabit large expanses of Pacific estuarine tide flats, from British Columbia to Baja California. The spatial distribution of shrimp populations within estuaries has rarely been quantified because ...

249

Environmental forcing on jellyfish communities in a small temperate estuary.  

PubMed

The impact of biological, hydrodynamic and large scale climatic variables on the jellyfish community of Mondego estuary was evaluated from 2003 to 2010. Plankton samples were collected at the downstream part of the estuary. Siphonophora Muggiaea atlantica and Diphyes spp. were the main jellyfish species. Jellyfish density was generally higher in summer and since 2005 densities had increased. Summer community analysis pointed out Acartia clausi, estuarine temperature and salinity as the main driven forces for the assemblage's structure. Also, Chl a, estuarine salinity, runoff and SST were identified as the major environmental factors influencing the siphonophores summer interannual variability. Temperature influenced directly and indirectly the community and fluctuation of jellyfish blooms in the Mondego estuary. This study represents a contribution to a better knowledge of the gelatinous plankton communities in small temperate estuaries. PMID:22770533

Primo, Ana Lígia; Marques, Sónia C; Falcão, Joana; Crespo, Daniel; Pardal, Miguel A; Azeiteiro, Ulisses M

2012-06-23

250

BACTERIOPLANKTON DYNAMICS IN A SUBTROPICAL ESTUARY: EVIDENCE FOR SUBSTRATE LIMITATION  

EPA Science Inventory

Bacterioplankton abundance and metabolic characteristics were measured along a transect in Pensacola Bay, Florida, USA, to examine the factors that control microbial water column processes in this subtropical estuary. The microbial measures included 3 H-L-leucine incorporation, e...

251

OXYGEN UPTAKE AND NUTRIENT REGENERATION IN THE PECONIC ESTUARY  

EPA Science Inventory

EXECUTIVE SUMMARY: OXYGEN UPTAKE AND NUTRIENT REGENERATION IN THE PECONIC ESTUARY Rates of oxygen consumption and nutrient regeneration were measured annually throughout the Peconic Estuarine System. Sediment and water column oxygen uptake were measured to determine the potential...

252

Biogeochemistry of the Kem' River estuary, White Sea (Russia)  

Microsoft Academic Search

The biogeochemistry of the river-sea interface was studied in the Kem' River (the largest river flowing to the White Sea from Karelian coast) estuary and adjacent area of the White Sea onboard the RV \\

V. R. Shevchenko; Y. S. Dolotov; N. N. Filatov; T. N. Alexeeva; A. S. Filippov; E.-M. Nöthig; A. N. Novigatsky; L. A. Pautova; A. V. Platonov; N. V. Politova; T. N. Rat'kova; R. Stein

2005-01-01

253

Water Quality and Wastewater Loadings, Upper Potomac Estuary during 1969.  

National Technical Information Service (NTIS)

The report has been developed to provide the conferees and others interested the current status of the water quality, wastewater loading and control needs. The scope of this report is limited to current conditions (1969) in the Potomac Estuary.

N. A. Jaworski

1969-01-01

254

Columbia River Estuary Inventory of Physical, Biological and Cultural Characteristics.  

National Technical Information Service (NTIS)

This inventory contains summaries of the physical, biological and cultural characteristics of the Columbia River estuary area. It is intended to be a primary resource for the development of the CREST Land and Water Use Plan and contains information pertin...

1977-01-01

255

Ecology of Tijuana Estuary, California: An Estuarine Profile.  

National Technical Information Service (NTIS)

Tijuana Estuary in southern California is characterized by a high degree of environmental variability resulting primarily from unpredictable freshwater inputs. The report discusses these habitats and synthesizes data amassed on the vegetation, algae, inve...

J. B. Zedler C. S. Nordby

1986-01-01

256

Mathematical Model Studies of Water Quality in the Potomac Estuary.  

National Technical Information Service (NTIS)

Mathematical models are becoming an increasingly important 'tool' for predicting, under a variety of conditions, water quality behavior in an estuary. The purpose of this report is to present recent Chesapeake Technical Support Laboratory studies on use o...

K. D. Feigner L. J. Clark

1972-01-01

257

The ecology of Tijuana Estuary, California: An estuarine profile  

SciTech Connect

This is the first attempt to synthesize and interpret a rapidly growing data base on the estuary's diverse biota - its vegetation, algae, birds, fishes, and invertebrates. Because so many changes have occurred in response to recent catastrophic events, we describe how each aspect of the estuary appeared before 1980 and how it has responded to several perturbations. The experimental tests of these cause-effect relationships have not been completed, and there is little reason to expect that environmental conditions have stabilized or that new types of disturbances won't occur. Thus, this profile should be viewed as a stage in the process of understanding Tijuana Estuary. Like the estuary itself, our knowledge is continuously evolving.

Zedler, J.B.; Nordby, C.S.

1986-06-01

258

DOWNSTREAM MIGRATION OF SALMONID SMOLTS IN OREGON RIVERS AND ESTUARIES  

EPA Science Inventory

Migratory fish passage is an important designated use for many Oregon estuaries. Acoustic transmitters were implanted in coho smolts in 2004 and 2006 to evaluate how estuarine habitat, and habitat loss, might affect population health. Acoustic receivers that identified individu...

259

Macroalgal bloom dynamics in a highly eutrophic southern California estuary  

Microsoft Academic Search

A 16-mo long monitoring study was carried out in Upper Newport Bay estuary (UNB), Orange County, California, to quantify the\\u000a macroalgal community of a southern California estuary. Quarterly sampling began December 1996 at 8 stations along the main\\u000a channel and tidal creeks ranging from the head to the lower end of UNB. At each station, two strata (one at high

Krista Kamer; Karleen A. Boyle; Peggy Fong

2001-01-01

260

Sediment transport by streams draining into the Delaware Estuary  

USGS Publications Warehouse

The quantity of sediment transported by streams draining into the Delaware estuary from Pennsylvania, New Jersey, and Delaware varies areally according to geology, physiography, and land use. Of the estimated total sediment load of 1.6 million tons entering the Delaware estuary annually, about 48 percent is contributed by the Delaware River main stem at Trenton, NJ; 34 percent by Pennsylvania tributaries; and 18 percent by New Jersey and Delaware tributaries.

Mansue, Lawrence J.; Commings, Allen B.

1974-01-01

261

Particle–water interactions of organic nitrogen in turbid estuaries  

Microsoft Academic Search

The hypothesis that particle–water interactions of organic nitrogen (ON) in turbid estuaries are controlled by specific fractions of suspended particulate matter (SPM) has been tested. Suspended particles from the turbidity maximum zone of a temperate, macro-tidal estuary were separated by gravitational settling to yield permanently suspended (PSPM; 46–51% of the total SPM load) and resuspendable (RSPM) particle fractions. Abiotic and

A. D. Tappin; G. E. Millward; M. F. Fitzsimons

2010-01-01

262

In Brief: Eutrophication stresses U.S. estuaries  

NASA Astrophysics Data System (ADS)

A 31 July NOAA report on estuarine eutrophication, or nutrient pollution, indicates moderate to high level nutrient-related impacts in 64 of 99 U.S. estuaries that had adequate data for evaluation. Lead author Suzanne Bricker of NOAA's Center for Coastal Monitoring and Assessment said that most problems in the estuaries are related to human activities. The report, completed in partnership with the University of Maryland Center for Environmental Science, calls for improved management, monitoring, research, and communication efforts.

Showstack, Randy

2007-08-01

263

A century of fish research in South African estuaries  

Microsoft Academic Search

The history of South African estuarine ichthyology from 1910–2010 is reviewed. The first survey of fishes in a South African estuary was undertaken by Gilchrist in the early 1900s, followed by an extended period between the two world wars when little or no work was conducted in South African estuaries. In the 1940s and 1950s a series of surveys initiated

A K Whitfield

2010-01-01

264

St. Lucie Estuary and Indian River Lagoon conceptual ecological model  

Microsoft Academic Search

The St. Lucie Estuary is one of the largest brackish water bodies on the east coast of Florida, USA and a major tributary\\u000a to southern Indian River Lagoon. The Indian River Lagoon is a biogeographic transition zone, rich in habitats and species,\\u000a with the greatest species diversity of any estuary in North America. Habitats and species diversity in the lagoon

Patti Sime

2005-01-01

265

Attenuation of rare earth elements in a boreal estuary  

NASA Astrophysics Data System (ADS)

This study focuses on attenuation of rare earth elements (REE) when a boreal creek, acidified and loaded with REE and other metals as a result of wetland drainage, empties into a brackish-water estuary (salinity < 6‰). Surface water was collected in a transect from the creek mouth to the outer estuary, and settling (particulate) material in sediment traps moored at selected locations in the estuary. Ultrafiltration, high-resolution ICP-MS and modeling were applied on the waters, and a variety of chemical reagents were used to extract metals from the settling material. Aluminium, Fe and REE transported by the acidic creek were extensively removed in the inner/central estuary where the acidic water was neutralised, whereas Mn was relatively persistent in solution and thus redistributed to particles and deposited further down the estuary. The REE removal was caused by several contemporary mechanisms: co-precipitation with oxyhydroxides (mainly Al but also Fe), complexation with flocculating humic substances and sorption to suspended particles. Down estuary the dissolved REE pool, remaining after removal, was fractionated: the <1 kDa pool became depleted in the middle REE and the colloidal (0.45 ?m-1 kDa) pool depleted in the middle and heavy REE. This fractionation was controlled by the removal process, such that those REE with highest affinity for the settling particles became most depleted in the remaining dissolved pool. Modeling, based on Visual MINTEQ version 3.0 and the Stockholm Humic Model after revision and updating, predicted that the dissolved (<0.45 ?m) REE pool in the estuary is bound almost entirely to humic substances. Acid sulphate soils, the source of the REE and other metals in the creek water, are widespread on coastal plains worldwide and therefore the REE attenuation patterns and mechanisms identified in the studied estuary are relevant for recognition of similar geochemical processes and conditions in a variety of coastal locations.

Åström, Mats E.; Österholm, Peter; Gustafsson, Jon Petter; Nystrand, Miriam; Peltola, Pasi; Nordmyr, Linda; Boman, Anton

2012-11-01

266

Factors affecting longitudinal dispersion in estuaries of different scale  

Microsoft Academic Search

Traditionally, the overall diluting capacity of an estuary is characterized using a coefficient of longitudinal dispersion, K xe, which is given by the ratio of the dispersive flux of a dissolved substance to its tidally averaged longitudinal gradient. A steady-state model, which assumes a balance between the dispersive and non-dispersive fluxes and an exponential increase in estuary cross-sectional area towards

Roy E. Lewis; Reginald J. Uncles

2003-01-01

267

Yeast community survey in the Tagus estuary.  

PubMed

The yeast community in the waters of the Tagus estuary, Portugal, was followed for over a year in order to assess its dynamics. Yeast occurrence and incidence were measured and this information was related to relevant environmental data. Yeast occurrence did not seem to depend upon tides, but river discharge had a dramatic impact both on the density and diversity of the community. The occurrence of some yeasts was partially correlated with faecal pollution indicators. Yeast isolates were characterized by microsatellite primed PCR (MSP-PCR) fingerprinting and rRNA gene sequencing. The principal species found were Candida catenulata, C. intermedia, C. parapsilosis, Clavispora lusitaniae, Debaryomyces hansenii, Pichia guilliermondii, Rhodotorula mucilaginosa and Rhodosporidium diobovatum. The incidence of these species was evaluated against the environmental context of the samples and the current knowledge about the substrates from which they are usually isolated. PMID:16329949

de Almeida, João M G C F

2005-07-01

268

Hyperspectral imaging of rivers and estuaries  

NASA Astrophysics Data System (ADS)

The Hyperspectral Imager for the Coastal Ocean (HICO) is the first spaceborne imaging spectrometer designed to sample the coastal ocean. HICO samples selected coastal regions at 92 m ground sample distance with full spectral coverage (88 channels covering 400 to 900 nm) and a high signal-to-noise ratio to resolve the complexity of the coastal ocean. HICO has been operating on the International Space Station since October 2009 and collected over 8000 scenes for more than 50 users. We have been using HICO data to study major rivers and estuaries in the US and Asia. Our results show the advantages of HICO's additional spectral channels and higher spatial resolution for studying these complex coastal waters. We use these data to suggest requirements for spatial and spectral sampling for future ocean color sensors.

Davis, Curtiss O.; Tufillaro, Nicholas

2013-09-01

269

Columbia Bay, Alaska: an 'upside down' estuary  

USGS Publications Warehouse

Circulation and water properties within Columbia Bay, Alaska, are dominated by the effects of Columbia Glacier at the head of the Bay. The basin between the glacier terminus and the terminal moraine (sill depth of about 22 m) responds as an 'upside down' estuary with the subglacial discharge of freshwater entering at the bottom of the basin. The intense vertical mixing caused by the bouyant plume of freshwater creates a homogeneous water mass that exchanges with the far-field water through either a two- or a three-layer flow. In general, the glacier acts as a large heat sink and creates a water mass which is cooler than that in fjords without tidewater glaciers. The predicted retreat of Columbia Glacier would create a 40 km long fjord that has characteristics in common with other fjords in Prince William Sound. ?? 1988.

Walters, R. A.; Josberger, E. G.; Driedger, C. L.

1988-01-01

270

A review of solar-powered Stirling engines and low temperature differential Stirling engines  

Microsoft Academic Search

This article provides a literature review on solar-powered Stirling engines and low temperature differential Stirling engines technology. A number of research works on the development of Stirling engines, solar-powered Stirling engines, and low temperature differential Stirling engines is discussed. The aim of this review is to find a feasible solution which may lead to a preliminary conceptual design of a

Bancha Kongtragool; Somchai Wongwises

2003-01-01

271

Aging and sediment characteristics of northern Gulf of Mexico estuaries  

SciTech Connect

Eight major estuarine systems present along the northern margin of the Gulf of Mexico serve as primary depositional basins for all rivers draining into the gulf from central Louisiana eastward to the Florida peninsula. These estuaries consist of Apalachicola Bay, St. Andrews Bay, Choctawhatchee Bay, Pensacola Bay, Perdido Bay, Mobile Bay, Mississippi sound, and Lake Pontchartrainn. Because each receives sediment from a different river system (or systems), each estuary is characterized by sediments that are both physically and mineralogically distinct. Estuaries in the eastern Gulf, for example, possess a clay mineral suite dominated by kaolinite (derived from deeply weathered piedmont rocks), whereas those from the western Gulf are rich in smectite and mixed layer clays (reflecting a Western Interior or provenance from Paleozoic or older coastal plain sources). Similarly, weathering of rocks in the southern piedmont has provided eastern Gulf estuarine sediments with a suite of largely metamorphic rock-derived heavy minerals, whereas those in the western Gulf contain a mixed suite of both igneous- and metamorphic-derived minerals. Equally distinctive, however, are the textures of the bottom sediments themselves for each estuary when plotted on standard sand-silt-clay ternary diagrams. The relative percentages of these components are uniquely different for most of the estuaries and reflect both natural and anthropogenic conditions that exist in the watershed areas that drain into each estuary.

Isphording, W.C. (Univ. of South Alabama, Mobile (USA)); Imsand, F.D. (Army Corps of Engineers, Mobile, AL (USA)); Flowers, G.C. (Tulane Univ., New Orleans, LA (USA))

1989-09-01

272

Winds and the orientation of a coastal plane estuary plume  

NASA Astrophysics Data System (ADS)

Based on a calibrated coastal plane estuary plume model, ideal model hindcasts of estuary plumes are used to describe the evolution of the plume pattern in response to river discharge and local wind forcing by selecting a typical partially mixed estuary (the Cape Fear River Estuary or CFRE). With the help of an existing calibrated plume model, as described by Xia et al. (2007), simulations were conducted using different parameters to evaluate the plume behavior type and its change associated with the variation of wind forcing and river discharge. The simulations indicate that relatively moderate winds can mechanically reverse the flow direction of the plume. Downwelling favorably wind will pin the plume to the coasts while the upwelling plume could induce plume from the left side to right side in the application to CFRE. It was found that six major types of plumes may occur in the estuary and in the corresponding coastal ocean. To better understand these plumes in the CFRE and other similar river estuary systems, we also investigated how the plumes transition from one type to another. Results showed that wind direction, wind speed, and sometimes river discharge contribute to plume transitions.

Xia, Meng; Xie, Lian; Pietrafesa, Leonard J.

2010-10-01

273

Conservation of Thane Creek and Ulhas River Estuary, India.  

PubMed

There has been a steady decrease in the area occupied by wetlands in creeks and estuaries adjacent urban areas due to unprecedented urban growth in coastal cities, for example, Thane Creek and Ulhas River Estuary near Mumbai, India. Urban cities serve as centres of employment and attract a large number of migrants from other places. In case of coastal cities, due to inadequate infrastructure, wastewater and solid waste are disposed of into wetlands and estuary. Discharge of sediments and solid waste into the creeks from drains and construction activities has resulted in decreased flow depth in the coastal waters of Thane Creek and Ulhas River Estuary. Various researchers have studied individual elements of Thane Creek and Ulhas River Estuary at micro level. However, a holistic approach for restoration and conservation of the creek and estuary is required. This paper presents the details of an integrated approach incorporating different conservation measures such as sewerage and sewage treatment, urban drainage management, solid waste management, mangrove plantation and dredging. PMID:21117428

Nikam, Vinay S; Kumar, Arun; Lalla, Kamal; Gupta, Kapil

2009-07-01

274

Expendable Gas Turbine Engine Technology Advances.  

National Technical Information Service (NTIS)

New materials and component technologies are undergoing feasibility assessment in expendable gas turbine demonstrator engines. The new technologies, developed under the Integrated High Performance Turbine Engine Technologies (IHPTET) and other initiatives...

G. S. Cruzen

1994-01-01

275

Columbia River Estuary data development program: tidal marsh plant production in the Columbia River Estuary. Final report  

SciTech Connect

This report summarizes the final results of the Emergent Plant Primary Production Work Unit of the Columbia River Estuary Data Development Program (CREDDP). The report describes the species composition, standing crop, and production dynamics of the extensive areas of tidal marsh vegetation that fringe the shores of the Columbia River Estuary and form many of its islands. The role of marsh production is discussed within a conceptual framework of the entire estuarine ecosystem.

Macdonald, K.B.; Winfield, T.P.

1984-06-01

276

From the utilization point of view, the two approaches seem to United States Air Force 611th Air Support Group/Civil Engineering Squadron, Elmendorf AFB, Alaska. Remedial investigation and feasibility study Point Barrow Radar Installation, Alaska. Final report  

SciTech Connect

This report presents the findings of Remedial Investigations and Feasibility Studies at sites located at the Point Barrow radar installation in northern Alaska. The sites were characterized based on sampling and analyses conducted during Remedial Investigation activities performed during August and September 1993.

Karmi, S.

1996-02-19

277

United States Air Force 611th Air Support Group/Civil Engineering Squadron, Elmendorf AFB, Alaska. Remedial investigation and feasibility study: Oliktok Point Radar Installation, Alaska. Volume 1. (Includes appendices a - b)  

SciTech Connect

This report presents the findings of Remedial Investigations and Feasibility Studies at sites located at the Oliktok Point radar installation in northern Alaska. The sites were characterized based on sampling and analyses conducted during Remedial Investigation activities performed during August and September 1993.

NONE

1996-04-15

278

Evaluating Cumulative Ecosystem Response to Restoration Projects in the Lower Columbia River and Estuary, 2009  

SciTech Connect

This is the sixth annual report of a seven-year project (2004 through 2010) to evaluate the cumulative effects of habitat restoration actions in the lower Columbia River and estuary (LCRE). The project, called the Cumulative Effects Study, is being conducted for the U.S. Army Corps of Engineers Portland District (USACE) by the Marine Sciences Laboratory of the Pacific Northwest National Laboratory (PNNL), the Pt. Adams Biological Field Station of the National Marine Fisheries Service (NMFS), the Columbia River Estuary Study Taskforce (CREST), and the University of Washington. The goal of the Cumulative Effects Study is to develop a methodology to evaluate the cumulative effects of multiple habitat restoration projects intended to benefit ecosystems supporting juvenile salmonids in the 235-km-long LCRE. Literature review in 2004 revealed no existing methods for such an evaluation and suggested that cumulative effects could be additive or synergistic. From 2005 through 2009, annual field research involved intensive, comparative studies paired by habitat type (tidal swamp versus marsh), trajectory (restoration versus reference site), and restoration action (tidegate replacement vs. culvert replacement vs. dike breach).

Johnson, Gary E.; Diefenderfer, Heida L.; Borde, Amy B.; Bryson, Amanda J.; Cameron, April; Coleman, Andre M.; Corbett, C.; Dawley, Earl M.; Ebberts, Blaine D.; Kauffman, Ronald; Roegner, G. Curtis; Russell, Micah T.; Silva, April; Skalski, John R.; Thom, Ronald M.; Vavrinec, John; Woodruff, Dana L.; Zimmerman, Shon A.

2010-10-26

279

A hydrologic and geomorphic model of estuary breaching and closure  

NASA Astrophysics Data System (ADS)

To better understand how the hydrology of bar-built estuaries affects breaching and closing patterns, a model is developed that incorporates an estuary hydrologic budget with a geomorphic model of the inlet system. Erosion of the inlet is caused by inlet flow, whereas the only morphologic effect of waves is the deposition of sand into the inlet. When calibrated, the model is able to reproduce the initial seasonal breaching, seasonal closure, intermittent closures and breaches, and the low-streamflow (closed state) estuary hydrology of the Carmel Lagoon, located in Central California. Model performance was tested against three separate years of water-level observations. When open during these years, the inlet was visually observed to drain directly across the beach berm, in accordance with model assumptions. The calibrated model predicts the observed 48-h estuary stage amplitude with root mean square errors of 0.45 m, 0.39 m and 0.42 m for the three separate years. For the calibrated model, the probability that the estuary inlet is closed decreases exponentially with increasing inflow (streamflow plus wave overtopping), decreasing 10-fold in probability as mean daily inflow increases from 0.2 to 1.0 m3/s. Seasonal patterns of inlet state reflect the seasonal pattern of streamflow, though wave overtopping may become the main hydrologic flux during low streamflow conditions, infrequently causing short-lived breaches. In a series of sensitivity analyses it is seen that the status of the inlet and storage of water are sensitive to factors that control the storage, transmission, and inflow of water. By varying individual components of the berm system and estuary storage, the amount of the time the estuary is open may increase by 57%, or decrease by 44%, compared to the amount of time the estuary is open during calibrated model conditions for the 18.2-year model period. The individual components tested are: berm height, width, length, and hydraulic conductivity; estuary hypsometry (storage to stage relationship); two factors that control wave-swash sedimentation of the inlet; and sea level rise. The elevation of the berm determines the volume of water that must enter the estuary in order to breach, and it modulates the wave-overtopping flux and frequency. By increasing estuary storage capacity, the estuary will breach less frequently (- 27% change in time open for modeled excavation scenario) and store water up to 3 months later into the summer. Altering beach aquifer hydraulic conductivity affects inlet state, and patterns of breaching and water storage. As a result of sea-level rise of 1.67 m by 2100, and a beach berm that remains in its current location and accretes vertically, the amount of time the estuary remains open may decrease by 44%. Such a change is an end-member of likely scenarios given that the berm will translate landwards. Model results indicate that the amount of time the estuary is open is more sensitive to changes in wave run-up than the amount of sand deposited in the inlet per each overtopping wave.

Rich, Andrew; Keller, Edward A.

2013-06-01

280

3D engineered fiberboard : engineering analysis of a new building ...  

Treesearch

... three-dimensional sandwich panels, called '3D Engineered Fiberboard' are formed ... The proposed technology has a number or promising uses in construction, ... The economic feasibility of constructing panels from these materials is also ...

281

Tidal asymmetry in estuaries with mixed semidiurnal/diurnal tides  

NASA Astrophysics Data System (ADS)

Tidal asymmetry in estuaries with mixed, mainly semidiurnal tides arises from both the interaction of principal tides and the higher harmonics generated by distortions within the estuary. The duration asymmetry in rise and fall of water level caused by principal tides on the west coast of the continental United States is ebb-dominant, and so the tide entering estuaries is also ebb-dominant, prior to any internal distortions within the estuary. The interaction of higher harmonics with principal constituents either augments or cancels the duration asymmetry in the principal tides. In estuaries where tidal elevation and velocity phase are near quadrature (90° out of phase), the duration asymmetry in tidal elevation leads to asymmetries in tidal current magnitude. Asymmetry can be conveniently quantified in terms of the sample skewness, ?1, the normalized third sample moment about the mean. An analytic approximation to the skewness shows that traditional metrics of asymmetry, namely the ratio of constituent amplitudes and the relative constituent phase difference, arise from calculating the third sample moment. Observations from three California estuaries of different morphologies are presented as an illustration of how skewness can be used to quantify asymmetry in real systems. As in semidiurnal systems, morphology is a good predictor of whether higher harmonics engender ebb-dominance or flood-dominance, however asymmetry imposed by principal tides at the mouth must first be overcome and so there is a spatial evolution in the total asymmetry. Quantifying observations via skewness should be considered in addition to traditional metrics in estuaries with mixed tides.

Nidzieko, Nicholas J.

2010-08-01

282

The status of fish conservation in South African estuaries.  

PubMed

Estuary-dependent fish species are defined as those taxa whose populations would be adversely affected by the loss of estuarine habitats. Of the 155 species regularly recorded in South African estuaries, only 32 (21%) are completely dependent on these systems, but this figure increases to 103 species (66%) if partially dependent taxa are included in the analysis. The conservation of fishes in estuaries on the subcontinent is threatened by a number of factors, including habitat degradation, disruption of essential ecological processes, hydrological manipulations, environmental pollution, overexploitation due to fishing activities and, more recently, climate change and the effects of introduced aquatic animals. Although major threats to fishes are usually linked to environmental degradation, there is increasing evidence that the stocks of certain fish species are overexploited or collapsed. Fish conservation and fisheries management does not depend on the implementation of a single action, but rather the co-ordination of a detailed plan, often in a multidisciplinary context. Some examples of innovative means of contributing to estuarine fish conservation in a South African context include the determination and implementation of the ecological freshwater requirements for estuaries, the zoning of estuaries for different uses and the recognition that the maintenance of ecological processes are vital to aquatic ecosystem health. Apart from the designation of protected areas, the main direct means of conserving fish species and stocks include habitat conservation, controls over fishing methods, effort, efficiency and seasonality, pollution control and the prevention of artificial manipulation of estuary mouths. Since becoming a democracy in 1994, environmental legislation, policy and institutional arrangements in South Africa have undergone some major changes, which, if fully implemented, will be very positive for fish conservation in estuaries on the subcontinent. PMID:20557655

Whitfield, A K; Cowley, P D

2010-06-01

283

Columbia River Estuary Ecosystem Classification Hydrogeomorphic Reach  

USGS Publications Warehouse

Estuarine ecosystems are controlled by a variety of processes that operate at multiple spatial and temporal scales. Understanding the hierarchical nature of these processes will aid in prioritization of restoration efforts. This hierarchical Columbia River Estuary Ecosystem Classification (henceforth "Classification") of the Columbia River estuary is a spatial database of the tidally-influenced reaches of the lower Columbia River, the tidally affected parts of its tributaries, and the landforms that make up their floodplains for the 230 kilometers between the Pacific Ocean and Bonneville Dam. This work is a collaborative effort between University of Washington School of Aquatic and Fishery Sciences (henceforth "UW"), U.S. Geological Survey (henceforth "USGS"), and the Lower Columbia Estuary Partnership (henceforth "EP"). Consideration of geomorphologic processes will improve the understanding of controlling physical factors that drive ecosystem evolution along the tidal Columbia River. The Classification is organized around six hierarchical levels, progressing from the coarsest, regional scale to the finest, localized scale: (1) Ecosystem Province; (2) Ecoregion; (3) Hydrogeomorphic Reach; (4) Ecosystem Complex; (5) Geomorphic Catena; and (6) Primary Cover Class. For Levels 4 and 5, we mapped landforms within the Holocene floodplain primarily by visual interpretation of Light Detection and Ranging (LiDAR) topography supplemented with aerial photographs, Natural Resources Conservation Service (NRCS) soils data, and historical maps. Mapped landforms are classified as to their current geomorphic function, the inferred process regime that formed them, and anthropogenic modification. Channels were classified primarily by a set of depth-based rules and geometric relationships. Classification Level 5 floodplain landforms ("geomorphic catenae") were further classified based on multivariate analysis of land-cover within the mapped landform area and attributed as "sub-catena". The extent of detailed mapping is the interpreted Holocene geologic floodplain of the tidal Columbia River and its tributaries to the estimated head of tide. The extent of this dataset also includes tributary valleys that are not mapped in detail. The upstream extents of tributary valleys are an estimation of the limit of Columbia River influence and are for use as containers in future analyses. The geologic floodplain is the geomorphic surface that is actively accumulating sediment through occasional overbank deposition. Most features within the geologic floodplain are considered to be formed during the recent (Holocene-epoch) climatic regime. There are bedrock and pre-Holocene sedimentary deposits included where they are surrounded by Holocene sediment accumulations or have been shaped by Holocene floods. In some places, Holocene landforms such as landslides, tributary fans, and coastal dunes are mapped that extend outside of the modern floodplain. This map is not a floodplain hazard map or delineation of actual flood boundaries. Although wetlands are included in the Classification, they are based on different criteria than jurisdictional wetlands. The extent of mapping may differ from the actual limit of tidal influence.

Cannon, Charles M.; Ramirez, Mary F.; Heatwole, Danelle W.; Burke, Jennifer L.; Simenstad, Charles A.; O'Connor, Jim E.; Marcoe, Keith

2012-01-01

284

Columbia River Estuary Ecosystem Classification Geomorphic Catena  

USGS Publications Warehouse

Estuarine ecosystems are controlled by a variety of processes that operate at multiple spatial and temporal scales. Understanding the hierarchical nature of these processes will aid in prioritization of restoration efforts. This hierarchical Columbia River Estuary Ecosystem Classification (henceforth "Classification") of the Columbia River estuary is a spatial database of the tidally-influenced reaches of the lower Columbia River, the tidally affected parts of its tributaries, and the landforms that make up their floodplains for the 230 kilometers between the Pacific Ocean and Bonneville Dam. This work is a collaborative effort between University of Washington School of Aquatic and Fishery Sciences (henceforth "UW"), U.S. Geological Survey (henceforth "USGS"), and the Lower Columbia Estuary Partnership (henceforth "EP"). Consideration of geomorphologic processes will improve the understanding of controlling physical factors that drive ecosystem evolution along the tidal Columbia River. The Classification is organized around six hierarchical levels, progressing from the coarsest, regional scale to the finest, localized scale: (1) Ecosystem Province; (2) Ecoregion; (3) Hydrogeomorphic Reach; (4) Ecosystem Complex; (5) Geomorphic Catena; and (6) Primary Cover Class. For Levels 4 and 5, we mapped landforms within the Holocene floodplain primarily by visual interpretation of Light Detection and Ranging (LiDAR) topography supplemented with aerial photographs, Natural Resources Conservation Service (NRCS) soils data, and historical maps. Mapped landforms are classified as to their current geomorphic function, the inferred process regime that formed them, and anthropogenic modification. Channels were classified primarily by a set of depth-based rules and geometric relationships. Classification Level 5 floodplain landforms ("geomorphic catenae") were further classified based on multivariate analysis of land-cover within the mapped landform area and attributed as "sub-catena". The extent of detailed mapping is the interpreted Holocene geologic floodplain of the tidal Columbia River and its tributaries to the estimated head of tide. The extent of this dataset also includes tributary valleys that are not mapped in detail. The upstream extents of tributary valleys are an estimation of the limit of Columbia River influence and are for use as containers in future analyses. The geologic floodplain is the geomorphic surface that is actively accumulating sediment through occasional overbank deposition. Most features within the geologic floodplain are considered to be formed during the recent (Holocene-epoch) climatic regime. There are bedrock and pre-Holocene sedimentary deposits included where they are surrounded by Holocene sediment accumulations or have been shaped by Holocene floods. In some places, Holocene landforms such as landslides, tributary fans, and coastal dunes are mapped that extend outside of the modern floodplain. This map is not a floodplain hazard map or delineation of actual flood boundaries. Although wetlands are included in the Classification, they are based on different criteria than jurisdictional wetlands. The extent of mapping may differ from the actual limit of tidal influence.

Cannon, Charles M.; Ramirez, Mary F.; Heatwole, Danelle W.; Burke, Jennifer L.; Simenstad, Charles A.; O'Connor, Jim E.; Marcoe, Keith

2012-01-01

285

Columbia River Estuary Ecosystem Classification Ecosystem Complex  

USGS Publications Warehouse

Estuarine ecosystems are controlled by a variety of processes that operate at multiple spatial and temporal scales. Understanding the hierarchical nature of these processes will aid in prioritization of restoration efforts. This hierarchical Columbia River Estuary Ecosystem Classification (henceforth "Classification") of the Columbia River estuary is a spatial database of the tidally-influenced reaches of the lower Columbia River, the tidally affected parts of its tributaries, and the landforms that make up their floodplains for the 230 kilometers between the Pacific Ocean and Bonneville Dam. This work is a collaborative effort between University of Washington School of Aquatic and Fishery Sciences (henceforth "UW"), U.S. Geological Survey (henceforth "USGS"), and the Lower Columbia Estuary Partnership (henceforth "EP"). Consideration of geomorphologic processes will improve the understanding of controlling physical factors that drive ecosystem evolution along the tidal Columbia River. The Classification is organized around six hierarchical levels, progressing from the coarsest, regional scale to the finest, localized scale: (1) Ecosystem Province; (2) Ecoregion; (3) Hydrogeomorphic Reach; (4) Ecosystem Complex; (5) Geomorphic Catena; and (6) Primary Cover Class. For Levels 4 and 5, we mapped landforms within the Holocene floodplain primarily by visual interpretation of Light Detection and Ranging (LiDAR) topography supplemented with aerial photographs, Natural Resources Conservation Service (NRCS) soils data, and historical maps. Mapped landforms are classified as to their current geomorphic function, the inferred process regime that formed them, and anthropogenic modification. Channels were classified primarily by a set of depth-based rules and geometric relationships. Classification Level 5 floodplain landforms ("geomorphic catenae") were further classified based on multivariate analysis of land-cover within the mapped landform area and attributed as "sub-catena". The extent of detailed mapping is the interpreted Holocene geologic floodplain of the tidal Columbia River and its tributaries to the estimated head of tide. The extent of this dataset also includes tributary valleys that are not mapped in detail. The upstream extents of tributary valleys are an estimation of the limit of Columbia River influence and are for use as containers in future analyses. The geologic floodplain is the geomorphic surface that is actively accumulating sediment through occasional overbank deposition. Most features within the geologic floodplain are considered to be formed during the recent (Holocene-epoch) climatic regime. There are bedrock and pre-Holocene sedimentary deposits included where they are surrounded by Holocene sediment accumulations or have been shaped by Holocene floods. In some places, Holocene landforms such as landslides, tributary fans, and coastal dunes are mapped that extend outside of the modern floodplain. This map is not a floodplain hazard map or delineation of actual flood boundaries. Although wetlands are included in the Classification, they are based on different criteria than jurisdictional wetlands. The extent of mapping may differ from the actual limit of tidal influence.

Cannon, Charles M.; Ramirez, Mary F.; Heatwole, Danelle W.; Burke, Jennifer L.; Simenstad, Charles A.; O'Connor, Jim E.; Marcoe, Keith Marcoe

2012-01-01

286

Ceramic Materials in Piston Engines.  

National Technical Information Service (NTIS)

Properties of ceramic materials and suitability of ceramic components for diesel and spark-ignition engines are discussed and the present stage of preparedness and the feasibility of ceramic technology are evaluated in this literature review. Ceramic mate...

M. Kytoe N. O. Nylund

1986-01-01

287

Facilitation of the Estuary/Ocean Subgroup for Federal Research, Monitoring, and Evaluation, FY09 Annual Report  

SciTech Connect

This document is the annual report for fiscal year 2009 (FY09) for the project called Facilitation of the Estuary/Ocean Subgroup (EOS). The EOS is part of the research, monitoring, and evaluation (RME) effort developed by the Action Agencies (Bonneville Power Administration [BPA], U.S. Army Corps of Engineers [Corps or USACE], U.S. Bureau of Reclamation) in response to obligations arising from the Endangered Species Act as a result of operation of the Federal Columbia River Power System (FCRPS).

Johnson, Gary E.

2009-10-22

288

Building Regional Threat-Based Networks for Estuaries in the Western United States  

Microsoft Academic Search

Estuaries are ecologically and economically valuable and have been highly degraded from both land and sea. Estuarine habitats in the coastal zone are under pressure from a range of human activities. In the United States and elsewhere, very few conservation plans focused on estuaries are regional in scope; fewer still address threats to estuary long term viability.We have compiled basic

Matthew S. Merrifield; Ellen Hines; Xiaohang Liu; Michael W. Beck; Simon Thrush

2011-01-01

289

Habitat Use by Juvenile Salmonids in the Smith River Estuary, California  

Microsoft Academic Search

Estuaries are highly productive areas that serve as important nursery habitat for many species of fish. Estuaries provide juvenile salmonids Oncorhynchus spp. with foraging habitats, refuge from predators, and areas in which smoltification and orientation for return migrations can occur. Our primary goal was to describe how juvenile salmonids use the Smith River estuary in northern California, a system that

Rebecca M. Quiñones; Timothy J. Mulligan

2005-01-01

290

PEER REVIEW OF PECONIC ESTUARY PROGRAM HYDRODYNAMIC AND WATER QUALITY (EUTROPHICATION) MODEL  

EPA Science Inventory

The Peconic Estuary is located on the eastern end of Long Island, New York. Under the Federal Clean Water Act, the Peconic Estuary was named an "Estuary of National Significance" in 1992. Because of its high concentration of rare, threatened and endangered species and habitats,...

291

Sedimentation of river-transported particles in the Öre estuary, northern Sweden  

Microsoft Academic Search

Sedimentation of river transported particles in the Öre Estuary was studied during spring flow (April–May, 1989). River input was calculated as the product of discharge and particle concentration in the river water. The concentration of suspended matter in the estuary water was determined with a light-scattering probe at 25 depth profiles throughout the estuary. The sedimentation was measured using sediment

Louise Malmgren; Lars Brydsten

1992-01-01

292

An inventory of Australian estuaries and enclosed marine waters: an overview of results  

Microsoft Academic Search

The database shows that most estuaries in northern and western Australia have been relatively unaffected by human activity. In contrast, estuaries in eastern and southern Australia generally have lower water quality and greater catchment clearance and a high percentage face real threats to their conservation values. The estuaries in NSW and Victoria have the most extensive literature available. The results

Daniel J Bucher; Peter Saenger

1991-01-01

293

The distribution of Neomysis americana in the estuary of the Delaware River  

Microsoft Academic Search

Observations on the plankt onic shrimp, Neomysis americana (Smith), in the Delaware River estuary were carried out over a period of two years. It was found that Neomysis was far more ubllndant, in the deep water of the estuary than in the near-surface or shallow water. Moreover, it, was more abundant within the estuary than in the coastal waters at

EDWARD M. HULBURT

1957-01-01

294

The value of oral history in natural resource management: the Balcombe Estuary Reserve, Mount Martha, Victoria  

Microsoft Academic Search

This study investigates the benefits of using oral history as a tool for the sustainable management of estuaries. Twenty-two semi-structured interviews were conducted to generate oral history records for the Balcombe Estuary Reserve, a small estuary in a periurban zone on the Mornington Peninsula, Victoria. These interviews establish a more complete picture of changes in land use and ecological change

M. Semken; K. K. Miller; K. James

2011-01-01

295

Metals in sediments and benthic organisms in the Mersey estuary  

NASA Astrophysics Data System (ADS)

Concentrations of twelve metals were determined in sediments, seaweed ( Fucus vesiculosus), winkles ( Littorina littorea), polychaetes ( Nereis diversicolor), suspension feeding bivalves ( Mytilus edulis, Cerastoderma edule) and deposit feeding bivalves ( Macoma balthica, Scrobicularia plana) collected from the Mersey estuary between April 1980 and June 1984. Sediments and organisms in the Mersey are moderately contaminated with most of the metals measured, but mercury concentrations are consistently higher than in other United Kingdom estuaries. Comparisons with other sites in the North West of England indicate that mercury residues in organisms, though primarily dependent on sediment concentrations, are also influenced by complexation with particulate organic matter which reduces the availability of mercury. The biological availability of arsenic in Mersey sediments is similarly influenced by complexation with iron oxyhydroxides. Nereis diversicolor and Macoma balthica are the most suitable indicator species in terms of abundance and widespread distribution along the estuary, and, for the majority of metals, tissue concentrations increase upstream, reflecting corresponding gradients in sediment contamination. However mid-estuarine peaks for tin, chromium copper and nickel in Nereis indicate more localised inputs to the estuary. Correlations between lead in sediments and organisms are poor; it is suggested that hydrophilic alkyl lead compounds may be the predominant biologically available forms. Progressive reductions in mercury contamination in sediments and mercury and lead in organisms have occurred in recent years, which coincide with efforts to reduce inputs of these metals to teh Mersey estuary.

Langston, W. J.

1986-08-01

296

Nitrogenase gene expression in the Chesapeake Bay Estuary.  

PubMed

Like many estuaries, the Chesapeake Bay has pronounced gradients in salinity and nutrients. Previous studies have shown that there is a high diversity of nitrogenase (nifH) genes in the estuary, and that there are specific distributions of individual nifH phylotypes. In contrast to previous work that revealed the remarkable diversity of nifH phylotypes in the Chesapeake estuary, in this study of nifH expression we only detected two phylotypes, and both were phylogenetically related to cyanobacterial nifH genes. One of the phylotypes was closely related to a nifH sequence from the filamentous, heterocystous cyanobacterium Anabaena cylindrica, and was found at the head of the estuary. The other phylotype was found in a sample collected near the mouth of the estuary and was closely related to nifH sequences from Group A unicellular cyanobacteria, which has previously been reported in oceanic waters only. These nifH phylotypes had distinct patterns of expression that were restricted to different regions of the Chesapeake Bay. This study provides the first evidence of nifH expression in the Chesapeake Bay, and suggests that diazotrophic unicellular cyanobacteria have a broader distribution and activity than previously recognized. PMID:17504496

Short, Steven M; Zehr, Jonathan P

2007-06-01

297

Potential intertidal habitat restoration sites in the Duwamish River estuary  

SciTech Connect

Restoration of wetland habitats in highly urbanized areas is generally constrained by scarcity of opportunity, adverse impacts of surrounding land use, and cost. Although areal wetland losses approach 98% in Seattle's Duwamish River estuary, the system continues to support important salmonid runs, as well as a variety of bird and mammal species. Estuarine-dependent organisms are likely limited by quality and quantity of intertidal habitat in the system. Because the long-range, estuary-wide benefit of site-specific mitigation and restoration projects is limited, it is imperative to develop estuary-wide restoration plans. Towards this end, an inventory and analysis of potential intertidal habitat restoration sites has been completed for the Duwamish River estuary. Twenty-four sites, ranging in size from 0.8 to 25 acres were identified and comparative functional potential assessed. The majority of these sites (18) occur in the upper estuary. Two sites are located in Elliott Bay, and four are located near the historic mouth of the river in the vicinity of Harbor Island. Spatial data have been developed in geographic information system (GIS) format. Other site-specific data relative to habitat restoration has also been assembled.

Tanner, C.D.

1991-12-01

298

Dissolved Humic Matter in Arctic Estuaries  

NASA Astrophysics Data System (ADS)

As part of the German-Russian bilateral SIRRO(Siberian River Runoff)-project we studied the distribution of dissolved humic matter isolated by XAD-8 in the estuarine waters of the Ob and Yenisei rivers. The relative contributions of humic matter carbon to total DOC decreased from 61-77 percent in the river freshwater endmember to 35-40 percent in the marine waters of the open Kara Sea at salinities 33 psu. Humic carbon mixed conservatively in the Yenisei and non-conservatively in the Ob, where partial removal was indicated in the low salinity range. Changes in the relative contribution of humic matter to different molecular weight classes of DOM (ultrafiltration cutoffs 150 KDa, 450 KDa, 800 KDa) were studied along the salinity gradient in the Yenisei. High molecular weight DOM is relatively enriched in humics in fresh-water compared to sea-water HMW-DOM. Low molecular weight DOM is realtively enriched in humics in sea-water compared to fresh-water LMW-DOM. Throughout the estuary humic matter is depleted in 13C and nitrogen compared to total DOM, reflecting a dominant soil source. We estimate an annual input of 5 Tg humic matter carbon by the two rivers into the Kara Sea.

Spitzy, A.; Koehler, H.; Ertl, S.

2002-12-01

299

Shallow Sediment Trace Metal Concentrations and Short-Term Accumulation Rates in the Neponset River Estuary, Massachusetts, USA  

Microsoft Academic Search

The Neponset River estuary is a small estuary that drains into the Boston Harbor on the east coast of the United States. It is also a highly urbanized estuary and has a long history of urban development over 450 years. In July 2006, six sediment cores were collected in the Neponset River estuary to examine particle dynamics and sediment accumulation

J. R. Spencer; J. Zhu; C. R. Olsen

2010-01-01

300

The buffering capacity of a small estuary on nutrient fluxes originating from its catchment (Leyre estuary, SW France)  

NASA Astrophysics Data System (ADS)

This work studied the impact of a small estuary (a 4 km-long estuary, at the interface between the Leyre River and the Arcachon lagoon, SW France) with a short flushing time on continental nutrient loads to a coastal lagoon. While large estuaries are known to modify the nutrient load of rivers to the coast, the impact on continental fluxes of a short salinity gradient from small coastal rivers is rarely studied. A survey of nutrient and dissolved organic matter concentration, particulate phosphorus speciation and particulate organic matter (POM) concentration and characteristics (C:N ratio and particulate organic carbon ?13C) showed that the estuarine behaviour varied throughout the year. The autochthonous primary production was a sink of dissolved N, P and Si in spring. During this period, the continental load of dissolved nitrogen was reduced by about 1/3 and phosphorus was totally consumed by estuarine processes. Nutrient recycling occurred in summer with ammonium production although this source was low in comparison with continental fluxes of nitrogen. The phosphorus concentration was dominated by the iron oxides-bound fraction. Contrary to large estuaries, the desorption of particulate phosphorus was not a source of dissolved phosphorus. Our results showed that estuarine processes impacted the net nutrient fluxes during productive periods, although estuarine residence time was very short. Passive transport with conservative mixing of nutrient was observed in autumn and winter. The non-conservative behaviour of small estuaries must be taken into account for nutrient mass balance calculation in lagoon.

Canton, Mathieu; Anschutz, Pierre; Poirier, Dominique; Chassagne, Romain; Deborde, Jonathan; Savoye, Nicolas

2012-03-01

301

Elemental analysis of sediments from the Severn Estuary  

NASA Astrophysics Data System (ADS)

Measurements of heavy metals in the Severn Estuary (UK) sediments are reported. The particle induced X-ray emission (PIXE) technique was employed to analyse the sediments from the estuary. Thick targets were prepared from core samples collected from Purton, Portishead and Clevedon sites along the estuary and then bombarded with a 2.5 MeV proton beam from the 3 MV Dynamitron accelerator housed at the Radiation Centre of the School of Physics and Space Research. The concentrations of the heavy metals were deduced by analysing the emitted characteristic X-rays. Initial results of this study are presented in this paper and are compared with other measurements. Practical minimum detection limits for such analyses are also discussed.

Sokhi, R. S.; Davis, A.; Randle, K.; West, J. R.; West, M. S.

1990-04-01

302

The validation of ecosystem models of turbid estuaries  

NASA Astrophysics Data System (ADS)

The ecosystem model of the Bristol Channel and Severn Estuary (GEMBASE) was fitted to 3 years of survey data, and has subsequently been validated against a further 5 years of monitoring data. A control chart technique clearly demonstrates that the model is, on the whole, an adequate representation of the estuarine carbon cycle, although the precision of model estimates reduces with increasing trophic level. An ecosystem model of the Ems Estuary has been adapted to simulate the Severn Estuary, and the impact of introducing a notional tidal power scheme assessed. The results were compared to those obtained using GEMBASE in the Severn. The broad predictions from both models are in agreement, although some detail is at variance, which implies that the fundamental ecological assumptions of the models are compatible.

Radford, P. J.; Ruardij, P.

1987-11-01

303

Does boat traffic cause displacement of fish in estuaries?  

PubMed

Estuaries are increasingly under threat from a variety of human impacts. Recreational and commercial boat traffic in urban areas may represent a significant disturbance to fish populations and have particularly adverse effects in spatially restricted systems such as estuaries. We examined the effects of passing boats on the abundance of different sized fish within the main navigation channel of an estuary using high resolution sonar (DIDSON). Both the smallest (100-300mm) and largest (>501mm) size classes had no change in their abundance following the passage of boats. However, a decrease in abundance of mid-sized fish (301-500mm) occurred following the passage of boats. This displacement may be attributed to a number of factors including noise, bubbles and the rapidly approaching object of the boat itself. In highly urbanised estuarine systems, regular displacement by boat traffic has the potential to have major negative population level effects on fish assemblages. PMID:23938471

Becker, Alistair; Whitfield, Alan K; Cowley, Paul D; Järnegren, Johanna; Næsje, Tor F

2013-08-09

304

A Feasibility Study.  

National Technical Information Service (NTIS)

A feasibility study has produced a sporozoite-induced rodent malaria test system that is based on the mortality rather than on the morbidity of negative controls. The test is performed with the NK65 strain of Plasmodium berghei, Anopheles stephensi and IC...

D. S. Rane

1975-01-01

305

Radium isotopes in the Orinoco estuary and Eastern Caribbean Sea  

SciTech Connect

Radium isotopes provide a means of identifying the source of freshened waters in the ocean and determining the time elapsed since these waters were in the estuary. The authors present evidence that during April, waters from the Amazon mixing zone pass within 50 km of the mouth of the Orinoco River. These Amazon waters are characterized by a lower [sup 228]Ra/[sup 226]Ra activity ratio (AR) than are waters from the Orinoco at similar salinities. During autumn, the increased discharge of the Orinoco displaces the freshened Amazon waters seaward, yet the two can be distinguished clearly. Within the Caribbean Sea, waters of Orinoco origin carry a characteristic radium signature including excess activities of [sup 224]Ra. This isotope may be used to estimate the time elapsed since the waters were removed from contact with sediments. Current speeds based on [sup 224]Ra dating ranged from 15 to 33 cm/s during April. The radium isotopes also provide an assessment of sediment mixing in the estuary. During low discharge (April), considerable mixing of older sediment by physical or biological processes or dredging maintained high activities of [sup 228]Ra in the estuary and produced the highest [sup 228]Ra/[sup 226]Ra AR's yet measured in any estuary. During high discharge (September), a large fraction of the [sup 228]Ra was derived from desorption from fresh sediment rather than mixing of older sediments. Activities of [sup 224]Ra were high in the estuary during both high and low discharge, indicating that considerable mixing of recently introduced sediment must occur during each period. During April, [sup 224]Ra and [sup 228]Ra activities in the water were about equal, indicating that most of the sediment being resuspended had been stored in the estuary long enough to reestablish radioactive equilibrium in the [sup 232]Th decay series (i.e., 20 years). 19 refs., 11 figs., 3 tabs.

Moore, W.S.; Todd, J.F. (Univ. of South Carolina, Columbia (United States))

1993-02-15

306

Modeling pesticide fate in a small tidal estuary  

USGS Publications Warehouse

The exposure analysis modeling system (EXAMS), a pesticide fate model developed by the U.S. Environmental Protection Agency, was modified to model the fate of the herbicides atrazine and metolachlor in a small tidally dominated estuary (Bath Creek) in North Carolina, USA where freshwater inflow accounts for only 3% of the total flow. The modifications simulated the changes that occur during the tidal cycle in the estuary, scenarios that are not possible with the original EXAMS model. Two models were created within EXAMS, a steady-state model and a time-variant tidally driven model. The steady-state model accounted for tidal flushing by simply altering freshwater input to yield an estuary residence time equal to that measured in Bath Creek. The tidal EXAMS model explicitly incorporated tidal flushing by modifying the EXAMS code to allow for temporal changes in estuary physical attributes (e.g., volume). The models were validated with empirical measurements of atrazine and metolachlor concentrations in the estuary shortly after herbicide application in nearby fields and immediately following a rain event. Both models provided excellent agreement with measured concentrations. The steady-state EXAMS model accurately predicted atrazine concentrations in the middle of the estuary over the first 3 days and under-predicted metolachlor by a factor of 2-3. The time-variant, tidally driven EXAMS model accurately predicted the rise and plateau of both herbicides over the 6-day measurement period. We have demonstrated the ability of these modified EXAMS models to be useful in predicting pesticide fate and exposure in small tidal estuaries. This is a significant improvement and expansion of the application of EXAMS, and given the wide use of EXAMS for surface water quality modeling by both researchers and regulators and the ability of EXAMS to interface with terrestrial models (e.g., pesticide root zone model) and bioaccumulation models, we now have an easily-accessible and widely accepted means of modeling chemical fate in estuaries. ?? 2006 Elsevier B.V. All rights reserved.

McCarthy, A. M.; Bales, J. D.; Cope, W. G.; Shea, D.

2007-01-01

307

Human Impact on Estuaries: A Terrible Spill in Grand Bay  

NSDL National Science Digital Library

In this activity, learners make a model of a pollution spill that occurred at Bangs Lake in Mississippi and measure water quality parameters in their model. Learners then study the actual spill, analyzing various forms of data to determine the date of the spill and identify how the spill changed water quality parameters in the estuary during and after the spill. Learners speculate on how various life forms in the estuary were affected. Finally, learners produce a timeline of the spill event, with recommendations to the state Department of Environmental Quality about how to prevent large-scale pollution spills like this in the future.

Terc; National Oceanic and Atmospheric Administration (NOAA)

2012-07-24

308

Information on Estuaries: National Estuarine Research Reserve System  

NSDL National Science Digital Library

Created by Congress in 1972, the National Estuarine Research Reserve System (NERRS) is dedicated to fostering a system of estuary reserves that represents the wide range of coastal and estuarine habitats found in the United States and its territories. Currently 425,000 acres in 18 states and Puerto Rico are protected by NERRS. Following the brief introduction to estuaries on the homepage is a link to a clickable map of NERRS Sites in the United States. Each NERRS site maintains a homepage with information on the reserves such as the site description, current research, and educational and resource management projects.

309

Tidal currents and bedload transport at the mouth of a rock-bound estuary during low river discharge conditions (Guadiana Estuary, Portugal)  

Microsoft Academic Search

The present study documents the poorly-described hydro-sediment dynamics of narrow bedrock-controlled estuaries during periods of low-river discharge. The results also contribute to assess the geomorphological evolution of these systems, when affected by drastic flow regulation. The Guadiana Estuary is a narrow rock-bound mesotidal estuary, 80 km in length, located at the southern border between Spain and Portugal. Until recently, the

E. Garel; A. Pacheco; Ó. Ferreira

2009-01-01

310

Optical properties of a tropical estuary during wet and dry conditions in the Nha Phu estuary, Khanh Hoa Province, south-east Vietnam  

Microsoft Academic Search

There has been a strong research focus on optical properties in temperate estuaries but very much less in tropical estuaries.\\u000a These properties comprise light and beam attenuation dominated by suspended particulate matter, Chl a, and CDOM. Spatially and temporally distributed data on optical properties in a tropical wet and dry estuary are compared\\u000a and discussed in relation to those of

Lars Chresten Lund-Hansen; Doan Nhu Hai; Nguyen Ngoc Lam; Morten Holtegaard Nielsen

2010-01-01

311

Research, Monitoring, and Evaluation for the Federal Columbia River Estuary Program  

SciTech Connect

The purpose ofthis document is to describe research, monitoring, and evaluation (RME) for the Federal Columbia River Estuary Program. The intent of this RME effort is to provide data and information to evaluate progress toward meeting program goals and objectives and support decision-making in the Estuary Program. The goal of the Estuary Program is to understand, conserve, and restore the estuary ecosystem to improve the performance of listed salmonid populations. The Estuary Program has five general objectives, designed to fulfill the program goal, as follows. 1. Understand the primary stressors affecting ecosystem controlling factors, such as ocean conditions and invasive species. 2. Conserve and restore factors controlling ecosystem structures and processes, such as hydrodynamics and water quality. 3. Increase the quantity and quality of ecosystem structures, i.e., habitats, juvenile salmonids use during migration through the estuary. 4. Maintain the food web to benefit salmonid performance. 5. Improve salmonid performance in terms of life history diversity, foraging success, growth, and survival. The goal of estuary RME is to provide pertinent and timely research and monitoring information to planners, implementers, and managers of the Estuary Program. In conclusion, the estuary RME effort is designed to meet the research and monitoring needs of the estuary Program using an adaptive management process. Estuary RME's success and usefulness will depend on the actual conduct of adaptive management, as embodied in the objectives, implrementation, data, reporting, and synthesis, evaluation, and decision-making described herein.

Johnson, Gary E.; Diefenderfer, Heida L.; Ebberts, Blaine D.; Tortorici, Cathy; Yerxa, Tracey; Leary, J.; Skalski, John R.

2008-02-05

312

The chemical oceanographic consequences of environmental restoration projects in the Golden Horn estuary (Marmara Sea, Turkey).  

PubMed

The input of industrial and domestic waste to the horizontal circulation in the Golden Horn Estuary of Marmara Sea has resulted in one of the most polluted estuaries in the past. Consequently, the dissolved oxygen concentrations in both the surface and bottom waters decreased toward to the estuary head during 1998-2005. In contrast, the total suspended solids content of the surface water decreased toward to the estuary mouth. However, construction of the operational collector system surrounding the estuary during the process of rehabilitation projects, combined with the opening of the middle pontoons of the Valide Sultan Bridge, resulted in gradually improved water quality of the estuary with a concomitant decrease in pollution. However, phytoplankton blooms and eutrophication persist especially in the innermost part of the Golden Horn in 2005. The region from the estuary mouth up to Camialti has a dynamic structure, and sufficient circulation seemingly occurs in this part of the Golden Horn. PMID:19353286

Balkis, N; Müftüo?lu, E; Aksu, A; Sur, H I; Apak, R

2009-04-08

313

Environmental management of a highly impacted, urbanized tropical estuary: rehabilitation and restoration  

NASA Astrophysics Data System (ADS)

The principles of the dynamics and interrelationships within the dominant subtropical and tropical Caribbean seagrass community have been studied previously before, during, and after impact. From these and scores of observations of damage and recovery patterns in Thalassia ecosystems, a sense of management recovery strategy has emerged. Artificial restoring of Thalassia testudinum seeds into areas cut off from stock (fruit, seeds) appeared feasible on a large scale after the Turkey Point (Biscayne Bay, Miami, Florida) restoration and test sampling throughout North Biscayne Bay. Two large-scale seeding attempts were made; after 11 months they compared favorably with Turkey Point specimens with regard to growth parameters, despite the turbidity and other persistent pollution. Thus, the possible areas in which Thalassia seed restoration can be used has increased to include estuaries of multiple impact still in various stages of recovery after physical and sewage pollution. This technique should be especially useful to “developing” nations where important nearshore fisheries nurseries based on Thalassia ecosystems have been heavily damaged and now lie barren. Man's impact on the estuary where seed restoration was attempted includes the following activities: 50% of the bay bottom directly dredged or filled (leaving much unconsolidated sediment); 50 million gallons of domestic waste dumped directly into a low flushing part of the bay for 20 years; seven major causeways transecting the bay, restricting circulation and flushing; two artificial inlets made into navigational channels; freshwater sheet flow drastically changed due to channelization by flood-control canals; urban runoff from a million people entering the bay. Most of the impacts have now abated; however, their long-term effects remain.

Thorhaug, A.

1980-03-01

314

Spatial and temporal flushing time approach in estuaries influenced by river and tide. An application in Suances Estuary (Northern Spain)  

NASA Astrophysics Data System (ADS)

Since Water Policies around the world establish the need to manage the aquatic systems through the use of water bodies, a hydromorphological descriptor such as the flushing time may be utilized as a good homogeneity and water quality criterion to distinguish between different types of water bodies. In order to achieve this task, a methodological procedure has been proposed involving a hydrodynamic forcing analysis, an approach to calculate flushing time and a sensitivity analysis of the results applied to the Suances Estuary. This method allows taking into account the different spatial regions on an estuary and the temporal variations of the main forcing. Consequently, the role of bathymetry, freshwater river inflows and oceanic tides on the flushing time is investigated using a two-dimensional numerical model. The hydrodynamic module integrates the depth-averaged mass and momentum equations in the time and space domains as well the transport module solves the depth-averaged advection-diffusion equation. Both modules were calibrated and validated using field data collected during spring and neap tidal cycles. Water levels and current velocities were used in the hydrodynamic module while salinities were compared in the transport module. In order to characterize the spatial variation in water renewal conditions, several boxes were selected along the estuary to evaluate the flushing time. The mass reduction is monitored in time and the flushing time at each part of the estuary was computed for several scenarios and analyzed with a multi-sensitivity analysis.Most of the river estuary basins in Northern Spain are characterized by their small surface area, short length and steepness, leading to a rapid hydrological response to rainfall and, consequently, a high variability in the river flow. During extensive dry periods during which the river flow is very small, pollutants could remain for long periods in the estuary posing an environmental risk.

Bárcena, Javier F.; García, Andrés; Gómez, Aina G.; Álvarez, César; Juanes, José A.; Revilla, José A.

2012-10-01

315

CF6 Engine Performance Improvement.  

National Technical Information Service (NTIS)

As part of the NASA-sponsored Engine Component Improvement (ECI) Program, a feasibility analysis of performance improvement and retention concepts for the CF6-6 and CF6-50 engines was conducted and seven concepts were identified for development and ground...

W. A. Fasching

1982-01-01

316

Evaluation of Life History Diversity, Habitat Connectivity, and Survival Benefits Associated with Habitat Restoration Actions in the Lower Columbia River and Estuary, Annual Report 2009  

SciTech Connect

This report describes the 2009 research conducted under the U.S. Army Corps of Engineers (USACE or Corps) project EST-09-P-01, titled “Evaluation of Life History Diversity, Habitat Connectivity, and Survival Benefits Associated with Habitat Restoration Actions in the Lower Columbia River and Estuary.” The research was conducted by the Pacific Northwest National Laboratory, Marine Science Laboratory and Hydrology Group, in partnership with the University of Washington, School of Aquatic and Fishery Sciences, Columbia Basin Research, and Earl Dawley (NOAA Fisheries, retired). This Columbia River Fish Mitigation Program project, referred to as “Salmonid Benefits,” was started in FY 2009 to evaluate the state-of-the science regarding the ability to quantify the benefits to listed salmonids1 of habitat restoration actions in the lower Columbia River and estuary.

Diefenderfer, Heida L.; Johnson, Gary E.; Sather, Nichole K.; Skalski, John R.; Dawley, Earl M.; Coleman, Andre M.

2010-08-01

317

Feasibility of residential curtailment  

Microsoft Academic Search

The feasibility of residential curtailment plans which would lead to a reduction in gas consumption by residential customers is assessed. An average use curtailment plan as outlined in the staff proposal in PUCO Case No. 75-901-GA-C01 and curtailment plans based on historic use were analyzed. These approaches are characterized by the imposition of price penalties to induce conservation. The primary

J. R. Devanney; C. R. Scott; M. A. Walters; G. D. Ball; R. R. Konst

2008-01-01

318

COASTAL BEND BAYS & ESTUARIES PROGRAM IMPLEMENTATION REVIEW 2004  

EPA Science Inventory

The Coastal Bend Bays & Estuaries Program, Inc. (CBBEP) is a nonprofit 501(c)(3)organization. The CBBEP project area encompasses 12 counties coincident with the Coastal Bend Council of Governments and extends from the Land-Cut in the Laguna Madre, through the Corpus Christi Bay s...

319

SAN JUAN BAY ESTUARY, COMPREHENSIVE CONSERVATION AND MANAGEMENT PLAN  

EPA Science Inventory

This Comprehensive Conservation and Management Plan (CCMP) contains information about the overall health of the San Juan Bay Estuary (SJBE) as well as proposed solutions to identified problems. These solutions, or Action Plans, are the result of a more than 4-year process of cons...

320

PERSISTENCE OF AROCLOR (TRADE NAME) 1254 IN A CONTAMINATED ESTUARY  

EPA Science Inventory

The brief report summarizes the concentrations of PCB's in oyster tissue (Crassostrea virginica) observed from April 1969 to June 1976 at three locations in the Escambia Bay estuary, following elimination of an accidental leak of Aroclor 1254 from an industrial site. Data showed ...

321

CHEMICAL CARCINOGENS IN BIVALVE MOLLUSKS FROM OREGON ESTUARIES  

EPA Science Inventory

The research undertaken involved the use of indigenous populatons of bivalve mollusks as monitors for detecting and quantifying environmental benzo(s)pyrene (BAP) in Oregon estuaries. Short-term and long-term studies were conducted in order to establish baseline levels of BAP and...

322

Mercury bioaccumulation in organisms from three Puerto Rican estuaries  

Microsoft Academic Search

We analyzed mercury levels in shrimp (Palaemonetes sp.), Blue Crabs (Callinectes sp.), fish (Tarpon Megalops atlantica and Tilapia Tilapia mossambica), lizards (Ameiva exsul), Cattle Egret (Bubulcus ibis) and Moorhen (Gallinula chloropus) in three estuaries in Puerto Rico in 1988. There were no quantifiable concentrations greater than the method detection limit of mercury in shrimp, crabs and lizards from any site.

Joanna Burger; Keith Cooper; Jorge Saliva; D. Gochfeld; D. Lipsky; Michael Gochfeld

1992-01-01

323

Studies on the absorption spectra of plant pigments in estuaries  

Microsoft Academic Search

Absorption spectra of acetone-soluble plant pigments were obtained from several sources, including the overlying waters, epibenthic layers and sediments of two New England estuaries, the remains of Zostera marina and its epiphytes, and pure cultures of marine diatoms. Comparisons of the absorption spectra and various absorbance ratios revealed no significant differences in the extracts of pigments sampled from the overlying

John H. Tietjen

1970-01-01

324

Saltwater intrusion in the Pearl River Estuary during winter  

Microsoft Academic Search

An intensive observation and a three-dimensional finite-difference model of Environmental Fluid Dynamic Code were used to study saltwater intrusion in the Pearl River Estuary. The model simulation was carried out for December 2007 to February 2008, which covered the in situ observation. The model was forced by observed winds, tidal elevation at open boundaries, and river discharges from eight inlets

Wei Zhou; Lin Luo; Hongzhou Xu; Dongxiao Wang

2012-01-01

325

Biological Uptake of Dissolved Silica in the Amazon River Estuary  

Microsoft Academic Search

Approximately 25 percent of the dissolved silica carried by the Amazon River is depleted through diatom production in the inner estuary. Annual production of opaline frustules is estimated to be 15 million tons. However, few diatoms accumulate in modern shelf sediments and chemical recycling appears to be slight. Instead, many frustules apparently are transported landward into the river system, where

John D. Milliman; Edward Boyle

1975-01-01

326

Production studies in the Mackenzie River — Beaufort Sea estuary  

Microsoft Academic Search

Production studies were carried out in the Mackenzie River\\/Beaufort Sea estuary during the summer of 1986. Results indicate that there were two plankton communities. One was located near the river mouth and was characterized by high dissolved organic carbon, high bacterial activity and a community of amphipods. The second community was associated with high phytoplankton production off shore and with

T. R. Parsons; D. G. Webb; H. Dovey; R. Haigh; M. Lawrence; G. E. Hopky

1988-01-01

327

Hypoxia tolerance in two juvenile estuary-dependent fishes  

Microsoft Academic Search

Hypoxia events, or low dissolved oxygen (DO) conditions, occur frequently in North Carolina estuaries during the summer. These events may have harmful effects on important fish stocks, including spot (Leiostomus xanthurus) and Atlantic menhaden (Brevoortia tyrannus), but their consequences are not well understood. We investigated direct mortality due to hypoxia in juvenile spot and Atlantic menhaden to determine how the

Elizabeth L. Shimps; James A. Rice; Jason A. Osborne

2005-01-01

328

SUSCEPTIBILITY OF A NORTHEASTERN GULF OF MEXICO ESTUARY TO HYPOXIA  

EPA Science Inventory

Bottom water hypoxia is a common adverse consequence of nutrient enrichment in estuaries and coastal waters. To protect against hypoxia, it is helpful to know which waters are most susceptible to hypoxia. Hypoxia has been observed regularly in Pensacola Bay, a northeastern Gulf o...

329

FISH LARVAE OF THE ESTUARIES AND COAST OF CENTRAL MAINE  

Microsoft Academic Search

Seasonal sampling of fish larvae in the central Maine coast took 22 kinds of larvae; 17 were identified to species, 3 to family, and 2 were not identified. Larvae of a few highly abundant species were present in the winter and early spring. These hatched from demersal eggs and were concentrated in the upper estuaries. The remaining species were less

STANLEY B. CHENOWETH

1973-01-01

330

APPENDIX C - ADDITIONAL INFORMATION ON FLUSHING IN ESTUARIES  

EPA Science Inventory

Water residence time is an important determinant of the sensitivity of the response of estuaries and other water bodies to nutrient loading. A variety of terms such as residence time, flushing time, transit time, turnover time, and age are used to describe time scales for transpo...

331

Sediment pumping by tidal asymmetry in a partially mixed estuary  

Microsoft Academic Search

Observations collected at two laterally adjacent locations are used to examine the processes driving sediment transport in the partially mixed York River Estuary. Estimates of sediment flux are decomposed into advective and pumping components, to evaluate the importance of tidal asymmetries in turbulent mixing. At the instrumented location in the estuarine channel, a strong asymmetry in internal mixing due to

Malcolm E. Scully; Carl T. Friedrichs

2007-01-01

332

Are the fisheries in the Tagus estuary sustainable?  

Microsoft Academic Search

The comparative sustainability of seven Tagus estuary fisheries – beam trawl, boat dredge, nets for glass eel, gill nets, eel basket, squid jig and octopus traps – is analysed using RAPFISH. This technique relies upon ordination of scored attributes, grouped in fields that cover ecological, economic, social, technological and ethical sustainability, performed using multi-dimensional scaling. Fisheries were analysed within each

Filipa Baeta; Ana Pinheiro; Madalena Corte-Real; José Lino Costa; Pedro Raposo de Almeida; Henrique Cabral; Maria José Costa

2005-01-01

333

Impaired health of juvenile Pacific salmon migrating through contaminated estuaries  

Microsoft Academic Search

Juvenile chinook salmon (Oncorhynchus tshawytscha) and chum salmon (Oncorhynchus keta) accumulate polycyclic aromatic hydrocarbons, polychlorinated biphenyls and other chemical contaminants in tissues, fluids and stomach contents while utilizing contaminated estuaries of Puget Sound during their out-migration from fresh water to open ocean. Field studies show that they have impaired health (reduced immunocompetence, increased mortality after disease challenge, reduced growth) resulting

T. Collier; M. Arkoosh; E. Casillas; M. Myers; C. Stehr; J. Meador; J. Stein

2000-01-01

334

Do Sturgeon limit burrowing shrimp populations in Pacific Northwest estuaries?  

Technology Transfer Automated Retrieval System (TEKTRAN)

Green sturgeon (Acipenser medirostris) and white sturgeon (Acipenser transmontanus) are common seasonal inhabitants of coastal estuaries from California USA to British Columbia, Canada. Both species are anadromous spending significant portions of their lives at sea and in their natal streams, but t...

335

Tidal variability of lateral advection in a coastal plain estuary  

NASA Astrophysics Data System (ADS)

Tidal variability of lateral advection of momentum (vuy, where u and v are along-estuary and lateral flows, respectively, and the subindex indicates differentiation with respect to the cross-estuary direction) was investigated in a coastal plain estuary with observations at Hampton Roads, which is the transition between the James River and Chesapeake Bay. Towed current velocity profiles and hydrographic profiles were captured during 9 expeditions in 2004 and 2005, to determine the intratidal and spatial changes in lateral advection of momentum and its contribution to along-channel flow. Curvature effects and lateral density gradients were important in driving lateral circulation and in modifying intratidal lateral advection of momentum. Lateral advection had the same order of magnitude as the baroclinic pressure gradient. Its contribution to the along-channel momentum balance was greatest during or just after peak flood and weakest at the end of ebb. During peak flood and peak ebb, the spatial distribution of vuy was seaward at the southern (left) side near surface and at the northern side (right) near bed (looking up-estuary), and landward in the rest of the channel. During slack periods the vuy structures were mostly landward. Observations were in good agreement with analytical model results during peak ebb and flood, but inconsistent during slack periods. The discrepancies between model results and field measurements can be attributed to bathymetry-density gradient interactions, which enhanced ebb-to-flood asymmetries in the along-channel and lateral flow.

Basdurak, N. B.; Valle-Levinson, A.

2013-07-01

336

Multibiomarker assessment of three Brazilian estuaries using oysters as bioindicators  

Microsoft Academic Search

Oysters have been largely employed as bioindicators of environmental quality in biomonitoring studies. Crassostrea rhizophorae was selected to evaluate the health status of three estuarine areas impacted by anthropogenic activities along the Brazilian coast, in three estuarine complexes, ranging in latitude from 7 to 25°S. In each estuary three sites were sampled in Winter and in Summer: a site considered

F. X. Valdez Domingos; M. Azevedo; M. D. Silva; M. A. F. Randi; C. A. Freire; H. C. Silva de Assis; C. A. Oliveira Ribeiro

2007-01-01

337

Geochemical processes in the Yenisei River and Estuary  

Microsoft Academic Search

As a part of the Russian-German project “Siberian River-Runoff (SIRRO)” the major element composition of the dissolved load and the major and trace element composition of particulate load and bottom sediment of the Yenisei River and Estuary were analyzed and examined in context of the basin lithology and climate> In addition, the processes controlling the transformation of the river load

B. Beeskow; V. Rachold

2003-01-01

338

Estuarine habitat utilization by birds in Yaquina Estuary, Oregon  

EPA Science Inventory

A wide variety of bird species are highly dependent on intertidal wetland habitats. Because of this dependency, birds are viewed as important indicators of wetland structure and function. Wetlands in Yaquina Bay along with the tidal wetlands in other Pacific coastal estuaries r...

339

Electrochemical determination of dissolved uranium in Krka river estuary  

Microsoft Academic Search

The applicability of the previously developed method for electrochemical determination of dissolved uranium concentration has been tested on natural water samples taken from the Krka river estuary during various seasons and along different depth profiles. The method is based on the following treatment of the sample: destroying the uranyl-carbonato complexes by adjusting the pH to 3, enabling the formation of

R Djogi?; M Branica

2001-01-01

340

Emergency Water Pumping Station, Potomac Estuary, Washington, D.C.  

National Technical Information Service (NTIS)

The project proposes construction of 100 MGD emergency raw water intake, access road and temporary earthen-fill bridge located approximately 1,100 feet upstream of Chain Bridge on the Potomac Estuary. The project will assure an adequate supply of raw wate...

1973-01-01

341

Phosphorus Concentrations in the Pamlico River Estuary of North Carolina.  

National Technical Information Service (NTIS)

The Pamlico River is a naturally rich estuary that extends from Washington, North Carolina some 35 miles to enter the west side of Pamlico Sound. It is shallow (average depth 10.5 feet), and has only a six inch lunar tide. The natural levels of phosphorus...

J. E. Hobbie

1970-01-01

342

Invasion by stages in the St Louis River estuary  

EPA Science Inventory

The St. Louis River estuary is recognized as an invasive species “hotspot” - the harbor ranks among the top locations in the Great Lakes reporting the first occurrence of new, aquatic non-native species. To date, 18 non-native benthic invertebrate, 4 non-native crusta...

343

BIVALVES AS BIOMONITORS IN THE NEUSE RIVER AND ESTUARY  

EPA Science Inventory

In eastern North Carolina the Neuse River and Neuse Estuary have been heavily impacted by the byproducts of row crop and livestock agriculture, forestry operations, and industry as well as effluent from municipal wastewater treatment plants. Non-point pollutants derived from thes...

344

Fish Diseases of the Albemarle-Pamlico Estuary.  

National Technical Information Service (NTIS)

The concern of fisheries managers over disease problems that appear in important sport and commercial fishes in the Tar-Pamlico Estuary was the reason for the study. Through a monitoring program in the Tar-Pamlico River the investigators assessed the occu...

E. J. Noga M. J. Dykstra J. F. Levine

1989-01-01

345

Physical oceanography of the Río de la Plata Estuary, Argentina  

Microsoft Academic Search

The Río de la Plata drains the second largest basin of South America. It flows into the Atlantic Ocean generating an estuarine system of about 35, 000 km2, with only 5–15 m water depth. On the basis of temperature and salinity data from the last 29 years, property seasonality at the estuary were studied. Surface salinity distribution is controlled by

Raúl A. Guerrero; Eduardo M. Acha; Carlos A. Lasta

1997-01-01

346

ECOLOGICAL CONDITION OF ESTUARIES IN THE GULF OF MEXICO  

EPA Science Inventory

The Gulf of Mexico is a vast natural resource that encompasses the coastal areas of western Florida, Alabama, Mississippi, Louisiana and Texas, as well as a portion of Mexico. Many estuaries flow into the Gulf of Mexico and serve as nursery grounds for fish, habitat for a wide va...

347

Stream, lake, estuary, and ocean pollution, 2nd edition  

Microsoft Academic Search

This book, an updated version of the 1985 edition, contains thirteen chapters, beginning with a preface which provides the objective of the book. The primary objective is to offer a comprehensive survey of the biological, hydrological, mathematical, and biochemical aspects of stream, lake, estuary, and ocean pollution analysis. The book also contains ten appendices of useful tables and nomographs of

Nemerow

1991-01-01

348

STATISTICAL SUMMARY EMAP-ESTUARIES VIRGINIAN PROVINCE - 1991  

EPA Science Inventory

Annual monitoring of indicators of the ecological condition of bays and estuaries within the Virginian Province (Cape Cod, MA to Cape Henry, VA) was conducted by the U.S. EPA's Environmental Monitoring and Assessment Program (EMAP) during July, August, and September, 1991. ata we...

349

BENTHIC NUTRIENT FLUX IN A SMALL ESTUARY IN NORTHWESTERNFLORIDA (USA)  

EPA Science Inventory

Benthic Nutrient Flux in a Small Estuary in Northwestern Florida(USA).Gulf and Caribbean Research 18, 15-25, 2006. Benthic nutrient fluxes of ammonium (NH4+), nitrite/nitrate (NO2-+NO3-), phosphate (PO4-), and dissolved silica (DSi) were measured in Escambia Bay, an estuar...

350

MONITORING THE ECOLOGICAL CONDITION OF ESTUARIES IN THE UNITED STATES  

EPA Science Inventory

The purpose of the Environmental Monitoring and Assessment Program/Estuaries component (EMAP-E) is to determine status, extent, changes, and trends in ecological indicators of the condition of the nation's estuarine resources. onitoring in the Virginian (Mid-Atlantic) and Louisia...

351

Eelgrass Distribution in the Great Bay Estuary 2005. Final Report.  

National Technical Information Service (NTIS)

Eelgrass (Zostera marina) is an essential habitat for the Great Bay Estuary (GBE) because it provides food for wintering waterfowl and habitat for juvenile fish and shellfish. Eelgrass is the basis of an estuarine food chain that supports many of the recr...

F. Short

2007-01-01

352

Eelgrass Distribution in the Great Bay Estuary for 2009.  

National Technical Information Service (NTIS)

Eelgrass in the Great Bay Estuary in 2009 was once again present only in Great Bay itself and in Portsmouth Harbor. For the second year in a row, there was no eelgrass in Little Bay or in the Piscataqua River. In 2009, there was a continued loss of eelgra...

F. T. Short

2010-01-01

353

Eelgrass Distribution in the Great Bay Estuary 2003. Final Report.  

National Technical Information Service (NTIS)

Eelgrass (Zostera marina) is an essential habitat for the Great Bay Estuary (GBE) because it provides food for wintering waterfowl and habitat for juvenile fish. Eelgrass is the basis of an estuarine food chain that supports many of the recreationally, co...

F. Short

2005-01-01

354

Eelgrass Distribution in the Great Bay Estuary 2004. Final Report.  

National Technical Information Service (NTIS)

Eelgrass (Zostera marina) is an essential habitat for the Great Bay Estuary (GBE) because it provides food for wintering waterfowl and habitat for juvenile fish and shellfish. Eelgrass is the basis of an estuarine food chain that supports many of the recr...

F. Short

2006-01-01

355

Eelgrass Distribution in the Great Bay Estuary for 2010.  

National Technical Information Service (NTIS)

Eelgrass in the Great Bay Estuary in 2010 was once again mainly present in the Great Bay itself with limited distribution in Portsmouth Harbor. In 2010, Portsmouth Harbor experienced a 9% loss of eelgrass distribution since 2009, for a loss of 46.7% of th...

F. T. Short

2011-01-01

356

The chemistry of the Delaware estuary. General considerations  

Microsoft Academic Search

Many propertics were measured in the Delaware estuary from freshwater to its mouth (30~4, salinity). Distinctive mixing patterns in property-salinity plots illustrate predictable behavior for different parameters. For example, alkalinity always shows an expected positive linear relationship and dissolved organic carbon a negative linear relationship (indicative of con- scrvative mixing). In contrast, phosphate shows a nonlinear plot suggestive of an

JONATHAN H. SHARP; CHARLES H. CULBERSON; THOMAS M. CHURCH

1982-01-01

357

Acoustic sensor coverage variation due to water stratification in estuaries  

Microsoft Academic Search

Monitoring underwater environments is critical for future near-shore exploration and port security. The effectiveness of underwater acoustic sensor systems is affected by the water environment, as sharp gradients in salinity and temperature cause sound to refract and reflect. Sound transmission can be impaired in estuaries where the salinity of the water is highly variable in space, and tidal action causes

Hongyuan Shi; Dov Kruger

2009-01-01

358

ASSESSING THE ECOLOGICAL CONDITION OF VERACRUZ, MEXICO ESTUARIES  

EPA Science Inventory

Macauley, John, Hector A. Vasquez, George Craven and P. Thomas Heitmuller. In press. Assessing the Ecological Condition of Veracruz, Mexico Estuaries (Abstract). To be presented at the EPA Science Forum: Healthy Communities and Ecosystems, 1-3 June 2004, Washington, DC. 1 p. (ERL...

359

Sedimentologic history of the Loxahatchee River estuary, Florida  

SciTech Connect

Short-term and long-term history of sedimentation in the Loxahatchee River estuary was evaluated based on field sampling and observations, as well as on laboratory analyses of core borings taken through the Holocene sedimentary sequences within the estuary basin. In the main body of the estuary away from sandbars, the sedimentary sequences were dominated by bioturbated mud, or mottled muddy sand, to depths of about 30 centimeters below the sediment surface and by interlayered sand and mud with high-organic content below the bioturbated zone. The biological reworking of the near-surface sediment is interpreted as the result of increased marine influences, possibly associated with ''permanently'' opening and maintaining Jupiter Inlet since the late 1940's and with altered freshwater runoff. Sedimentation rates based on radiocarbon dates have decreased from 0.69 millimeter per year about 7000 years ago to about 0.25 millimeter per year 1000 years ago. Although this trend is associated with a decrease in the rate at which sea level has been rising, sedimentation rates nevertheless have not kept up with rises in sea level. Other evidence indicates that sediment is being provided to the estuary at much higher rates than it is actually accumulating, and this suggests that dynamic physical processes of circulation and flushing are inhibiting rapid sediment accumulation. 15 refs., 31 figs., 5 tabs.

Wanless, H.; Rossinsky, V. Jr.; McPherson, B.F.

1984-01-01

360

Structure and Function of South-east Australian Estuaries  

Microsoft Academic Search

An attempt is made to synthesize the geological properties, water quality attributes and aspects of the ecology of south-east Australian estuaries so as to provide a framework for addressing coastal management issues. The approach is based on the underlying causal factors of geology and morphology and more immediate environmental factors (e.g. salinity and sediments) which are associated with ecological distributions,

P. S Roy; R. J Williams; A. R Jones; I Yassini; P. J Gibbs; B Coates; R. J West; P. R Scanes; J. P Hudson; S Nichol

2001-01-01

361

Building Consensual Institutions: Networks and the National Estuary Program  

Microsoft Academic Search

Currently, many approaches to solving policy problems seek to create community-based, less coercive solutions that are creating the conditions for the birth of new regional governmental institutions. We argue that networks form the core of these emergent structures and that federal programs can play a positive role in developing local networks. Our empirical work compares networks in estuaries included in

Mark Schneider; John Scholz; Mark Lubell; Denisa Mindruta; Matthew Edwardsen

2003-01-01

362

Man's Impact on the Environment: The Estuary as an Ecosystem.  

ERIC Educational Resources Information Center

|This environmental education guide focuses on man's impact on the estuary. The program contained in the guide is developed around the following nine questions: (1) What is a definition of the ecosystem being investigated?; (2) What are some of the biotic and abiotic features of the ecosystem and how do these features interrelate?; (3) Where are…

Brevard County School Board, Cocoa, FL.

363

A Temporarily Anoxic Water Mass in an Alaska Estuary.  

National Technical Information Service (NTIS)

The note reports on the occurrence of a temporary anoxic condition in Little Port Walter Estuary on southern Baranoff Island, Alaska. The condition was observed on 4 October 1971, and the mass of anoxic water was abruptly flushed out of the bay sometime b...

J. R. Knull

1973-01-01

364

Osmium behavior in estuaries: the Lena River example  

Microsoft Academic Search

The behavior of dissolved osmium at the river\\/ocean interface was studied in the Lena River estuary. Dissolved osmium removal is observed at very low salinities. The loss is estimated to be 28% of the dissolved concentration of the river. The removal cannot be related to the flocculation of iron oxide-organic matter colloids, but occurs simultaneously with the loss of aluminum.

S. Levasseur; V. Rachold; J.-L. Birck; C. J. Allègre

2000-01-01

365

Osmium behavior in estuaries: the Lena River example  

Microsoft Academic Search

The behavior of dissolved osmium at the river\\/ocean interface was studied in the Lena River estuary. Dissolved osmium removal is observed at very low salinities. The loss is estimated to be 28% of the dissolved concentration of the river. The removal cannot be related to the flocculation of iron oxide–organic matter colloids, but occurs simultaneously with the loss of aluminum.

S Levasseur; V Rachold; J.-L Birck; C. J Allègre

2000-01-01

366

SARASOTA BAY NATIONAL ESTUARY PROGRAM, A FRAMEWORK FOR ACTION  

EPA Science Inventory

Sarasota Bay: Framework for Action was produced by the Sarasota Bay National Estuary Program to characterize the condition of Sarasota Bay and present preliminary options for Bay improvement. The publication is a precursor to the CCMP. Past destruction of sea grasses and mangrove...

367

PEAK STREAMFLOW - VIRGINIA PORTION OF THE ALBEMARLE-PAMLICO ESTUARY  

EPA Science Inventory

Peak discharge data from the U.S. Geological Survey (http://waterdata.usgs.gov/nwis-w/VA) for gaging stations within the Virginia portion of the Albemarle-Pamlico Estuary watershed. Record dates vary by gaging station. Data for each station are located in a text file named by sta...

368

DAILY STREAMFLOW - VIRGINIA PORTION OF THE ALBEMARLE-PAMLICO ESTUARY  

EPA Science Inventory

Daily mean discharge data from the U.S. Geological Survey (http://waterdata.usgs.gov/nwis-w/VA) for gaging stations within the Virginia portion of the Albemarle-Pamlico Estuary watershed. Record dates vary by gaging station. Data for each station are located in a text file named ...

369

Survey of Morphological Changes on Tidal Flats in Estuaries  

Microsoft Academic Search

Tidal flat areas in estuaries are affected by strong morphodynamics. Changes of sedimentation and erosion occur on very different time and spatial scales. These changes challenge the responsible authorities due to the high importance of sufficient navigation channel depths and the ecological importance of those unique zones. The Hamburg University of Technology in cooperation with the Hamburg Port Authority runs

Thorsten Albers; Nicole von Lieberman

2010-01-01

370

Biogeochemical value of managed realignment, Humber estuary, UK.  

PubMed

We outline a plausible, albeit extreme, managed realignment scenario ('Extended Deep Green' scenario) for a large UK estuary to demonstrate the maximum possible biogeochemical effects and economic outcomes of estuarine management decisions. Our interdisciplinary approach aims to better inform the policy process, by combining biogeochemical and socioeconomic components of managed realignment schemes. Adding 7494 ha of new intertidal area to the UK Humber estuary through managed realignment leads to the annual accumulation of a 1.2 x 10(5) t of 'new' sediment and increases the current annual sink of organic C and N, and particle reactive P in the estuary by 150%, 83% and 50%, respectively. The increase in intertidal area should also increase denitrification. However, this positive outcome is offset by the negative effect of enhanced greenhouse gas emissions in new marshes in the low salinity region of the estuary. Short-term microbial reactions decrease the potential benefits of CO(2) sequestration through gross organic carbon burial by at least 50%. Net carbon storage is thus most effective where oxidation and denitrification reactions are reduced. In the Humber this translates to wet, saline marshes at the seaward end of estuaries. Cost-benefit analysis (CBA) was used to determine the economic efficiency of the Extended Deep Green managed realignment. When compared to a 'Hold-the-Line' future scenario, i.e. the present state/extent of sea defences in the estuary, the CBA shows that managed realignment is cost effective when viewed on >25 year timescales. This is because capital costs are incurred in the first years, whereas the benefits from habitat creation, carbon sequestration and reduced maintenance costs build up over time. Over 50- and 100-year timescales, the Extended Deep Green managed realignment scenario is superior in efficiency terms. The increased sediment accumulation is also likely to enhance storage of contaminant metals. In the case of Cu, a metal that currently causes significant water quality issues, Cu removal due to burial of suspended sediment in realigned areas translates to a value of approximately pounds sterling 1000 a(-1) (avoided clean up costs). Although this is not formally included in the CBA it illustrates another likely positive economic outcome of managed realignment. Although we focus on the Humber, the history of reclamation and its biogeochemistry is common to many estuaries in northern Europe. PMID:16996577

Andrews, J E; Burgess, D; Cave, R R; Coombes, E G; Jickells, T D; Parkes, D J; Turner, R K

2006-09-25

371

Columbia River Estuary Ecosystem Classification — Concept and application  

USGS Publications Warehouse

This document describes the concept, organization, and application of a hierarchical ecosystem classification that integrates saline and tidal freshwater reaches of estuaries in order to characterize the ecosystems of large flood plain rivers that are strongly influenced by riverine and estuarine hydrology. We illustrate the classification by applying it to the Columbia River estuary (Oregon-Washington, USA), a system that extends about 233 river kilometers (rkm) inland from the Pacific Ocean. More than three-quarters of this length is tidal freshwater. The Columbia River Estuary Ecosystem Classification ("Classification") is based on six hierarchical levels, progressing from the coarsest, regional scale to the finest, localized scale: (1) Ecosystem Province; (2) Ecoregion; (3) Hydrogeomorphic Reach; (4) Ecosystem Complex; (5) Geomorphic Catena; and (6) Primary Cover Class. We define and map Levels 1-3 for the entire Columbia River estuary with existing geospatial datasets, and provide examples of Levels 4-6 for one hydrogeomorphic reach. In particular, three levels of the Classification capture the scales and categories of ecosystem structure and processes that are most tractable to estuarine research, monitoring, and management. These three levels are the (1) eight hydrogeomorphic reaches that embody the formative geologic and tectonic processes that created the existing estuarine landscape and encompass the influence of the resulting physiography on interactions between fluvial and tidal hydrology and geomorphology across 230 kilometers (km) of estuary, (2) more than 15 ecosystem complexes composed of broad landforms created predominantly by geologic processes during the Holocene, and (3) more than 25 geomorphic catenae embedded within ecosystem complexes that represent distinct geomorphic landforms, structures, ecosystems, and habitats, and components of the estuarine landscape most likely to change over short time periods.

Simenstad, Charles A.; Burke, Jennifer L.; O'Connor, Jim E.; Cannon, Charles; Heatwole, Danelle W.; Ramirez, Mary F.; Waite, Ian R.; Counihan, Timothy D.; Jones, Krista L.

2011-01-01

372

Morphodynamic evolution of the Xiaoqing River mouth: a Huanghe River-derived mixed energy estuary  

NASA Astrophysics Data System (ADS)

In an estuary, tidal, wave and other marine powers interact with the coast in different ways and affect estuary morphology as well as its evolution. In the Huanghe (Yellow) River estuaries and nearby delta, there are many small sediment-affected estuaries with a unique morphology, such as the Xiaoqing River estuary. In this study, we investigated the special evolution and genetic mechanism of the Xiaoqing River estuary by analyzing graphic and image data with a numerical simulation method. The results show that NE and NE-E tide waves are the main driving force for sandbar formation. Sediment shoals have originated from huge amounts of sediment from the Huanghe River, with consequent deposition at the Xiaoqing River mouth. The lateral suspended sediments beyond the river mouth move landward. Siltation takes place on the northern shoreline near the river mouth whereas erosion occurs in the south. The deposits come mainly from scouring of the shallow seabed on the northern side of the estuary. Storm surges speed up deposition in the estuary. Development of the sediment shoals has occurred in two steps involving the processes of growth and further southward extension. Although the southward shift increases the river curvature and length, the general eastward orientation of the estuary is unlikely to change. Processes on the adjacent shorelines do not affect the development of the sediment shoals. The study presents a morphodynamic evolutionary model for the Xiaoqing River estuary, with a long-term series cycle, within which a relatively short cycle occurs.

Huang, Haijun; Liu, Yanxia; Qiu, Zhongfeng

2012-09-01

373

Building regional threat-based networks for estuaries in the Western United States.  

PubMed

Estuaries are ecologically and economically valuable and have been highly degraded from both land and sea. Estuarine habitats in the coastal zone are under pressure from a range of human activities. In the United States and elsewhere, very few conservation plans focused on estuaries are regional in scope; fewer still address threats to estuary long term viability.We have compiled basic information about the spatial extent of threats to identify commonalities. To do this we classify estuaries into hierarchical networks that share similar threat characteristics using a spatial database (geodatabase) of threats to estuaries from land and sea in the western U.S. Our results show that very few estuaries in this region (16%) have no or minimal stresses from anthropogenic activity. Additionally, one quarter (25%) of all estuaries in this study have moderate levels of all threats. The small number of un-threatened estuaries is likely not representative of the ecological variability in the region and will require working to abate threats at others. We think the identification of these estuary groups can foster sharing best practices and coordination of conservation activities amongst estuaries in any geography. PMID:21387006

Merrifield, Matthew S; Hines, Ellen; Liu, Xiaohang; Beck, Michael W

2011-02-28

374

Explaining the Physical Relation of Estuaries Shape and Bankfull Flood Discharge  

NASA Astrophysics Data System (ADS)

Estimating flood discharge in the tidal region of estuaries is always difficult as most of the available gauging stations are installed much further upstream outside the tidal region. Inside the tidal region, it is hard to observe the river discharge accurately. In the morphology and hydrodynamic studies of estuaries, it is known that river discharge is one of the important parameters. Unfortunately, research on morphology and hydrodynamics in estuaries is done separately. Until today, little research has been done to identify the relationship between these two processes in alluvial estuaries, and to understand why certain relations in nature exist. This study aims to discover the physical explanation for the relation between the geometrical characteristics of estuaries and flood discharge. The relationship between the ideal estuary depth and fresh water discharge was analyzed in 13 estuaries around the world using a stepwise regression and the outcome was compared to Lacey's theory of hydraulic geometry. From the analysis, it shows that the ideal depth of the estuaries is a function to the bankfull flood discharge to the power of 1/3 to 1/2 which indicates an agreement with Lacey's formula. In order to verify the accuracy of the relation, more data on the morphology and hydrodynamics are required. Thus, existing and new measurement data from estuaries worldwide will be collected and compiled to strengthen the reliability of the finding. Keywords: estuaries, geometry, flood discharge, alluvial, tidal

Anak Gisen, Jacqueline Isabella; Savenije, Hubert H. G.

2013-04-01

375

Biogeochemistry of nutrients in an estuary affected by human activities: The Wanquan River estuary, eastern Hainan Island, China  

NASA Astrophysics Data System (ADS)

Nutrient dynamics were studied in the estuary of the Wanquan River, a tropical mountainous river system of Hainan Island, China, during 2006-2009. The nutrients measured included NO3-, NO2-, NH4+, PO43-, Si(OH)4, total dissolved nitrogen (TDN), total dissolved phosphorus (TDP), dissolved organic nitrogen (DON), and dissolved organic phosphorus (DOP). The Wanquan River showed great variation in nutrient levels, was enriched in dissolved inorganic nitrogen (DIN) and dissolved silicate, and depleted in PO43-. The levels of dissolved silicate were higher than average for tropical systems. As a consequence the DIN:PO43- and Si(OH)4:DIN ratios were higher than the Redfield ratio. DON accounted for 18% of TDN in the Wanquan River, and DOP represented approximately 61% of TDP.Nutrients in the Wanquan River estuary behave either conservatively or nonconservatively. Nutrient biogeochemistry in the estuary is affected by human activities in adjacent areas and heavy rainfall associated with typhoons. Phosphorus may be the potential limiting nutrient for phytoplankton growth. A simple steady-state box model showed that riverine input was the major source of nutrients to the estuary, which acted as a source of all nutrients except dissolved silicate, TDP, and DOP. The results indicate that substantial quantities of nitrogen and PO43- are transported to the coastal system, and suggest that dissolved silicate accumulates in the sediment or is transformed into other forms.

Li, Ruihuan; Liu, Sumei; Zhang, Guiling; Ren, Jingling; Zhang, Jing

2013-04-01

376

IMPACT OF ARTIFICIAL STRUCTURES ON BIODIVERSITY OF ESTUARIES: A CASE STUDY FROM COCHIN ESTUARY WITH EMPHASIS ON CLAM BEDS  

Microsoft Academic Search

Interannual and seasonal variability of the hydrographic parameters and distribution of Villorita sp. in the Cochin estuary was studied to assess the impact due to the construction of Thannermukkom bund. Results showed that periodical closing and opening of the bund had significant effect on different hydrographic parameters. Water temperature showed an increase during January to March and July to September;

A. U. ARUN

2005-01-01

377

Sediment transport and dispersion in a cool-temperate estuary and embayment, Saco River estuary, Maine, USA  

Microsoft Academic Search

The Saco River flows through a rock bound, mid-latitude estuary recognized as the primary source of sand to the Saco Bay barrier beach system. To better constrain the conditions under which the Saco River contributes sand to Saco Bay, three moorings equipped with current meters and a CTD were deployed inside and outside the Saco River jetty system, from April

L. L. Brothers; D. F. Belknap; J. T. Kelley; C. D. Janzen

2008-01-01

378

Dissolved and Particulate Hydrocarbons in the Loire Estuary, from the Riverine Zone to the External Estuary: Budget at Different Seasons  

Microsoft Academic Search

In order to investigate the fate and transport processes of hydrocarbons in estuarine and coastal environments, we have undertaken a study of different hydrocarbon species in both dissolved and particulate forms. This two years study has been conducted in the Loire estuary at different reference stations (riverine, injection of sewage effluents, maximum turbidity zone, open sea) and at different seasons

J. Tronczynski; J. C. Marty; P. Scribe; A. Saliot

1986-01-01

379

Thin film thermocouples for internal combustion engines  

Microsoft Academic Search

The feasibility of fabricating thin film thermocouples on internal combustion engine hardware was investigated. The goal was to find a procedure that would be useful for the measurement of the surface metal temperature of valves, valve seats, combustion chamber surfaces, cylinder walls, and piston heads during engine operation. The approach pursued was to coat the engine hardware material with an

Kenneth G. Kreider

1986-01-01

380

Biomedical engineering educational programs in Mexico City  

Microsoft Academic Search

Mexico has two major educational programs in biomedical engineering (BME), each with some emphasis on educating instrumentation and clinical engineers. However, because biomedical engineering is still an emerging discipline in Mexico, several questions have arisen that challenge the focus of these programs and the feasibility of their application. The central problem in Mexico when dealing with BME is the shortage

V. M. Carbajal Castaneda

1988-01-01

381

Estuary Data Mapper: A Stand-Alone Tool for Geospatial Data Access, Visualization and Download for Estuaries and Coastal Watersheds of the United States  

EPA Science Inventory

The US EPA Estuary Data Mapper (EDM; http://badger.epa.gov/rsig/edm/index.html) has been designed as a free stand-alone tool for geospatial data discovery, visualization, and data download for estuaries and their associated watersheds in the conterminous United States. EDM requi...

382

Estuary Data Mapper: A Stand-Alone Tool for Geospatial Data Access, Visualization and Download for Estuaries and Coastal Watersheds of the United States. (UNH)  

EPA Science Inventory

The US EPA Estuary Data Mapper (EDM; http://badger.epa.gov/rsig/edm/index.html) has been designed as a free stand-alone tool for geospatial data discovery, visualization, and data download for estuaries and their associated watersheds in the conterminous United States. EDM requi...

383

Response of the turbidity maximum zone to fluctuations in sediment discharge from river to estuary in the Changjiang Estuary (China)  

NASA Astrophysics Data System (ADS)

In the Changjiang Estuary, interactions between the sea and the river result in the development of a turbidity maximum zone (TMZ). Riverine sediments are an important source for TMZ formation. Since the 1960s, sediment discharge from the river basin to the estuary has decreased due to dam construction, water and soil conservation, and water diversion projects. Thirty-two Landsat images of the estuary, covering the period from 1979 to 2008, were collected to identify the TMZ response to sediment decline. A threshold value of suspended sediment concentration (SSC) of 0.7 kg/m3, corresponding to a spectrum reflectance of 5% of Landsat MSS band 7 and 7% of Landsat TM/ETM band 4, was used to identify the Changjiang Estuary TMZ. The TMZ area was then extracted from each image to investigate its temporal and spatial variations during the past 30 years. The images were grouped into five time series; the average TMZ area of each series was estimated. The results show that the TMZ area declined 23% from series (a) to series (e), responding to a 77% reduction in riverine sediment discharge. In addition, the TMZ had strong seasonal and tidal variations; it was generally larger during flood seasons than during dry seasons and during spring tides compared to neap tides. The spring/neap tidal cycle played a more important role in TMZ change than did the seasonal cycle. Due to the continued reduction of sediment discharge to the estuary resulting from dams already constructed and to those that will be constructed upstream in the Changjiang River, it is predicted that the TMZ area will continue decreasing and that the re-suspension of local sediments will play a more important role in the formation of the TMZ.

Jiang, Xuezhong; Lu, Bing; He, Yuhong

2013-10-01

384

Analytical and numerical analysis of tides and salinities in estuaries; part I: tidal wave propagation in convergent estuaries  

NASA Astrophysics Data System (ADS)

Analytical solutions of the momentum and energy equations for tidal flow are studied. Analytical solutions are well known for prismatic channels but are less well known for converging channels. As most estuaries have a planform with converging channels, the attention in this paper is fully focused on converging tidal channels. It will be shown that the tidal range along converging channels can be described by relatively simple expressions solving the energy and momentum equations (new approaches). The semi-analytical solution of the energy equation includes quadratic (nonlinear) bottom friction. The analytical solution of the continuity and momentum equations is only possible for linearized bottom friction. The linearized analytical solution is presented for sinusoidal tidal waves with and without reflection in strongly convergent (funnel type) channels. Using these approaches, simple and powerful tools (spreadsheet models) for tidal analysis of amplified and damped tidal wave propagation in converging estuaries have been developed. The analytical solutions are compared with the results of numerical solutions and with measured data of the Western Scheldt Estuary in the Netherlands, the Hooghly Estuary in India and the Delaware Estuary in the USA. The analytical solutions show surprisingly good agreement with measured tidal ranges in these large-scale tidal systems. Convergence is found to be dominant in long and deep-converging channels resulting in an amplified tidal range, whereas bottom friction is generally dominant in shallow converging channels resulting in a damped tidal range. Reflection in closed-end channels is important in the most landward 1/3 length of the total channel length. In strongly convergent channels with a single forward propagating tidal wave, there is a phase lead of the horizontal and vertical tide close to 90o, mimicking a standing wave system (apparent standing wave).

van Rijn, Leo C.

2011-11-01

385

Research, Monitoring, and Evaluation for the Federal Columbia River Estuary Program.  

SciTech Connect

The purpose of this document is to describe research, monitoring, and evaluation (RME) for the Federal Columbia River Estuary Program, hereafter called 'the Estuary Program'. The intent of this RME effort is to provide data and information to evaluate progress toward meeting program goals and objectives and support decision making in the Estuary Program. The goal of the Estuary Program is to understand, conserve, and restore the estuary ecosystem to improve the performance of listed salmonid populations. The Estuary Program has five general objectives, designed to fulfill the program goal, as follows: (1) Understand the primary stressors affecting ecosystem controlling factors, such as ocean conditions and invasive species. (2) Conserve and restore factors controlling ecosystem structures and processes, such as hydrodynamics and water quality. (3) Increase the quantity and quality of ecosystem structures, i.e., habitats, juvenile salmonids use during migration through the estuary. (4) Maintain the food web to benefit salmonid performance. (5) Improve salmonid performance in terms of life history diversity, foraging success, growth, and survival. The goal of estuary RME is to provide pertinent and timely research and monitoring information to planners, implementers, and managers of the Estuary Program. The goal leads to three primary management questions pertaining to the main focus of the Estuary Program: estuary habitat conservation and restoration. (1) Are the estuary habitat actions achieving the expected biological and environmental performance targets? (2) Are the offsite habitat actions in the estuary improving juvenile salmonid performance and which actions are most effective at addressing the limiting factors preventing achievement of habitat, fish, or wildlife performance objectives? (3) What are the limiting factors or threats in the estuary/ocean preventing the achievement of desired habitat or fish performance objectives? Performance measures for the estuary are monitored indicators that reflect the status of habitat conditions and fish performance, e.g., habitat connectivity, survival, and life history diversity. Performance measures also pertain to implementation and compliance. Such measures are part of the monitoring, research, and action plans in this estuary RME document. Performance targets specific to the estuary were not included in the 2007 draft Biological Opinion.

Johnson, Gary E.; Diefenderfer, Heida L. (Pacific Northwest National Laboratory)

2008-02-20

386

Summary report: Economic feasibility studies of alcohol fuel production processes  

Microsoft Academic Search

In 1983 SERI awarded six subcontracts to four engineering firms to conduct technical and economic feasibility studies of processes to convert lignocellulosic feedstocks into premium fuels (methanol and ethanol). In this report general conclusions are drawn about the status of alcohol fuels production from cellulosic feedstocks and detailed conclusions about the status, economics, research needs, and process steps. Stone and

J. D. Wright; T. Milne; M. E. Karpuk; S. Isaacs; W. Hoagland

1986-01-01

387

Movements of green sturgeon, Acipenser medirostris , in the San Francisco Bay estuary, California  

Microsoft Academic Search

Synopsis  The green sturgeon, Acipenser medirostris, is a long-lived, iteroparous, anadromous acipenserid that is native to the San Francisco Bay Estuary, California. Sub-adult\\u000a and adult fish are oceanic, but enter the estuary during the spring and remain through autumn. Little is known about green\\u000a sturgeon distribution within the estuary or what, if any, physical parameters influence their movements. We report the

John T. Kelly; A. Peter Klimley; Carlos E. Crocker

2007-01-01

388

Spatial and temporal patterns in sediment and water column nutrients in a eutrophic Southern California estuary  

Microsoft Academic Search

Quarterly field sampling was conducted to characterize variations in water column and sediment nutrients in a eutrophic southern\\u000a California estuary with a history of frequent macroalgal blooms. Water column and sediment nutrient measures demonstrated\\u000a that Upper Newport Bay (UNB) is a highly enriched estuary. High nitrate (NO3\\u000a ?) loads from the river entered the estuary at all sampling times with

Karleen A. Boyle; Krista Kamer; Peggy Fong

2004-01-01

389

Status of persistent organic pollutants in the sediment from several estuaries in China  

Microsoft Academic Search

Sediment samples from three estuaries on the east coast of China were analyzed for persistent organic pollutants. Total PCB, PAH, and DDT concentrations in the sediments from Minjiang, Jiulongjiang, and Zhujiang estuaries ranged from 2 to 14 ng\\/g, 400 to 1500 ng\\/g, and 6 to 73 ng\\/g, respectively, in the sediments from these estuaries. The sources of PAH contamination were

Dongxing Yuan; Dongning Yang; Terry L Wade; Yaorong Qian

2001-01-01

390

A Decade of Change in the Skidaway River Estuary. III. Plankton  

Microsoft Academic Search

The Skidaway River estuary, GA (USA), a tidally dominated subtropical system surrounded by extensive Spartina salt marshes, is experiencing steady increases in nutrients, chlorophyll, and particulate matter and decline in dissolved\\u000a oxygen, associated with cultural eutrophication. A long-term study is documenting changes in these parameters: previous papers\\u000a Verity (Estuaries 25:944–960, 2002a, Estuaries 25:961–975, b) reported on hydrography, nutrients, chlorophyll, and

Peter G. Verity; David G. Borkman

2010-01-01

391

Assimilating in-situ Measurements into a Reduced-Dimensionality Model of an Estuary Plume System  

Microsoft Academic Search

A very fast, model independent, fully non-linear extension to the reduced space Kalman filter has been recently proposed and demonstrated for the assimilation of the non-linear circulation in both a synthetic estuary and in the river-dominated Columbia River estuary. Here, we extend the application to another complex problem the simulation of a coupled estuary-plume system. Our data assimilation method is

S. Frolov; A. Baptista; T. Leen; Z. Lu; R. van der Merwe

2006-01-01

392

Response of Nereis diversicolor population (Polychaeta, Nereididae) to the pollution impact - Authie and Seine estuaries (France)  

NASA Astrophysics Data System (ADS)

A survey within the French National Programme of Ecotoxicology was carried out in 2002, 2003 and 2004 to study the response of Nereis diversicolor populations (Polychaeta, Nereididae) to the impact of pollution in the Authie estuary (non-contaminated site) and in the Seine estuary (contaminated site). In the period studied, the density varied from 672 ind. m -2 to 3584 ind. m -2 in the Authie estuary and from 80 ind. m -2 to 920 ind. m -2 in the Seine estuary. Biomass varied from 3.94 g m -2 (dry weight) in February 2004 to 38.0 g m -2 in August 2003 in the Authie estuary and from 3.4 g m -2 in February 2002 to 0.6 g m -2 in February 2004 in the Seine estuary. Density and biomass of the populations of N. diversicolor were consistently lower in the Seine estuary than in the Authie estuary. Size frequency histograms permit the analysis of the cohorts as well as the elaboration of the growth curves. For the individuals from the Authie estuary, the relation between dry weight (DW) and length L3 (prostomium, peristomium and chaetiger 1) was DW = 4.2205 L3 2.9832. For those from the Seine estuary, the relation between dry weight and L3 was DW = 0.4697e 1.7209L3. The individuals of N. diversicolor should belong to eight cohorts in Authie estuary (two cohorts each year) instead of six cohorts for those from the Seine estuary. These differences can be attributed to the effect of pollution on the population of N. diversicolor.

Gillet, P.; Mouloud, M.; Durou, C.; Deutsch, B.

2008-01-01

393

Abundance of Yellow-Phase American Eels in the Hudson River Estuary  

Microsoft Academic Search

Fisheries for American eel Anguilla rostrata occur mostly in estuaries, yet eel abundance in large estuaries is poorly understood and the methods for estimating eel density underdeveloped. During 1997–1999, mark–recapture experiments were conducted for six consecutive days at six sites spanning the 250-km tidal portion of the Hudson River estuary, New York. Each experiment comprised 36 baited eel traps arrayed

W. E. Morrison; D. H. Secor

2004-01-01

394

Crumb rubber feasibility report  

SciTech Connect

The Cumberland County supply region generates approximately 58,000 tons of scrap tires each year, equivalent to 45,000 tons of rubber after processing. Approximately 8,000 tons per year are in concentrated locations and can be easily collected. The costs of collection for the remainder vary significantly. Given current markets, economically feasible processes (ambient technology) can reprocess approximately 65 to 75 percent of the 37,000 tons into a marketable product. A processing plant sized for this supply would process 120 tons per day, a viable plant by industry standards. The end uses for whole tires constitute a negligible market, aside from the retreader market. Crumbed rubber is the major development efforts, there are potentially large opportunities in North Carolina.

NONE

1985-11-01

395

Macrobenthic community in the Xiaoqing River Estuary in Laizhou Bay, China  

NASA Astrophysics Data System (ADS)

The macrobenthic community of the Xiaoqing River Estuary and the adjacent sea waters was investigated in May and November 2008, August 2009, and May and September 2010, respectively. A total of 95 species of macrobenthos were identified in the five cruises and most of them were polychaetes (46.39%), mollusks (28.86%) and crustaceans (20.62%). The Shannon-Wiener index of macrobenthos was lower than 2 in 67% sites. Along the stream channel, estuary and the coastal waters, the species of polychaetes reduced gradually, while the abundance increased at first and then decreased. The abundance was the biggest at regions with salinity of 5-20 in the estuary. The species and abundance of mollusks and crustaceans increased gradually. As for seasonal distribution, the species, abundance and biomass were higher in spring and lower in summer and autumn. Contemporaneously compared with Laizhou Bay and Yellow River Estuary, the species of macrobenthos appeared in the Xiaoqing River Estuary were much less, while the percentage of polychaetes was higher. Abundance and biomass were higher in Xiaoqing River estuary, then consequently followed by Laizhou Bay and Yellow River Estuary. The dominant species in Xiaoqing River Estuary was polychaete, and Layzhou Bay mollusk. The community structure characteristics of macrobenthos in the Xiaoqing River Estuary revealed a significant pollution status in this region.

Luo, Xianxiang; Zhang, Shanshan; Yang, Jianqiang; Pan, Jinfen; Tian, Lin; Zhang, Longjun

2013-09-01

396

Effects of winds on stratification and circulation in a partially mixed estuary  

NASA Astrophysics Data System (ADS)

Numerical experiments are conducted to investigate how axial winds affect stratification and circulation in the partially mixed estuary of Chesapeake Bay. In the absence of rotational effects, stratification in the estuary decreases following both down-estuary and up-estuary winds, but stratification experiences larger reduction and takes longer to recover under up-estuary winds. In the presence of rotational effects, wind-driven lateral circulations cause the lateral straining of density field and weaken the shear in the along-channel flows. Under the down-estuary winds, a counterclockwise lateral circulation steepens isopycnals in the cross-channel sections, while the Coriolis force acting on it decelerates the downwind current in the surface layer and the upwind-directed current in the bottom layer. Under the up-estuary winds, a clockwise lateral circulation flattens isopycnals in the cross-channel sections and reduces the shear between the surface and bottom currents. Hence, in the presence of rotational effects, the lateral straining offsets the effects of longitudinal straining such that the asymmetry in stratification reduction is significantly reduced between the down-estuary and up-estuary winds. Regime diagrams based on Wedderburn (W) and Kelvin (Ke) numbers are constructed to summarize the net effects of winds on estuarine stratification during both wind perturbation and postwind adjustment periods.

Li, Yun; Li, Ming

2011-12-01

397

Circulation and Physical Processes within the San Gabriel River Estuary During Summer 2005  

USGS Publications Warehouse

The Southern California Coastal Water Research Project (SCCWRP) is developing a hydrodynamic model of the SGR estuary, which is part of the comprehensive water-quality model of the SGR estuary and watershed investigated by SCCWRP and other local agencies. The hydrodynamic model will help understanding of 1) the exchange processes between the estuary and coastal ocean; 2) the circulation patterns in the estuary; 3) upstream natural runoff and the cooling discharge from PGS. Like all models, the SGR hydrodynamic model is only useful after it is fully calibrated and validated. In May 2005, SCCWRP requested the assistance of the U.S. geological Survey (USGS) Coastal and Marine Geology team (CMG) in collecting data on the hydrodynamic conditions in the estuary during the summer dry season. The summer was chosen for field data collection as this was assumed to be the season with the greatest potential for chronic degraded water quality due to low river flow and high thermal stratification within the estuary (due to both higher average air temperature and PGS output). Water quality can be degraded in winter as well, when higher river discharge events bring large volumes of water from the Los Angeles basin into the estuary. The objectives of this project were to 1) collect hydrodynamic data along the SGR estuary; 2) study exchange processes within the estuary through analysis of the hydrodynamic data; and 3) provide field data for model calibration and validation. As the data only exist for the summer season, the results herein only apply to summer conditions.

Rosenberger, Kurt J.; Xu, Jingping; Stein, Eric D.; Noble, Marlene A.; Gartner, Anne L.

2007-01-01

398

Using a multi-component indicator toward reducing phytoplankton bloom occurrences in the Swan River estuary.  

PubMed

The Swan River estuary is an icon of the city of Perth, Western Australia, running through the city centre and dividing the northern from the southern part of the city. However, frequent phytoplankton blooms have been observed in the estuary as a result of eutrophication. The Index of Sustainable Functionality (ISF), a composite index able to indicate for sustainable health of the estuary, was applied, taking into account the hydrology and highly seasonal nature of the estuary to inform the management of the estuary, towards the aim of reducing bloom occurrences. The study period was from the beginning of intensive monitoring in 1995 to mid-2009. The results emphasize the importance of physical controls on the ecology of the estuary. No significant trend in the estuary's low functionality was found, indicating that despite extensive restoration efforts, the frequency of algal bloom occurrences has remained relatively stationary and other mitigating factors have maintained an annual average ISF value at around 70 % functionality. We identified that the low flow season consistently performs the worst, with (high) temperature found as the most dominant variable for phytoplankton growth and bloom. Thus in managing the estuary, vigilance is required during periods of high temperature and low flow. Focusing on the risk of phytoplankton bloom, a nutrient reduction program that is in place is a long term solution due to high concentrations in the estuary. Other management measures need to be considered and adopted to effectively reduce the occurrences of future phytoplankton blooms. PMID:22669343

Kristiana, Ria; Antenucci, Jason P; Imberger, Jorg

2012-06-05

399

Physico-chemical characteristics of the Vellar estuary in relation to shrimp farming.  

PubMed

All the physico-chemical parameters such as temperature, LEC, salinity, pH, dissolved oxygen and nutrients like total phosphorus, inorganic phosphate, nitrite and silicate studied in relation to shrimp farming. There are as many as 42 shrimp farms situated on the banks of Vellar estuary. These farms discharge the used water into the estuary, which may influence the biota there. In the present study the physico-chemical feature in relation to shrimp farming were studied in 3 stations of the estuary. When compared with the previous data from Vellar estuary there was no much difference in physico-chemical characteristics due to shrimp farming. PMID:12974418

Rajasegar, M

2003-01-01

400

Communications on Hydraulic and Geotechnical Engineering: Turbulent Free-Surface Flow over a Sill.  

National Technical Information Service (NTIS)

In civil engineering practice, flows in seas, estuaries, harbours and rivers are usually predicted by making use of hydraulic scale models or numerical models. The prediction of the effects of the Dutch Delta plan is one of the most important applications...

P. Blom

1993-01-01

401

Dwarf eelgrass, Zostera japonica: a malevolent, benevolent, or benign invasive ecosystem engineer?  

EPA Science Inventory

Dwarf eelgrass, Zostera japonica, is an introduced ecosystem engineering species first reported on the US west coast in 1957. In some US Pacific Northwest estuaries its areal coverage now exceeds that of the native eelgrass species, Zostera marina. Natural resource management?s...

402

Investigation of the Feasibility of Temperature Profiling Optical Diagnostics in the Ssme Fuel Pre-Burner.  

National Technical Information Service (NTIS)

Results of an analytical investigation to determine the feasibility of temperature profiling in the space shuttle main engine (SSME) fuel preburner are presented. In this application it is desirable to measure temperature in the preburner combustor with a...

J. A. Shirley

1983-01-01

403

Feasibility Study on Building and Operating a Fermentation Plant to Produce Monosodium Glutamate (MSG) (Final Report).  

National Technical Information Service (NTIS)

The feasibility study includes the development of a Monosodium Glutamate (MSG) market study, the process technology and engineering required to define the scope of building the plant, the cost of building and operating the plant, a project financial plan ...

2003-01-01

404

Feasibility Study. Gas Recovery Project. PDVSA-TDA. Volume 1. Conceptual Financing Plan.  

National Technical Information Service (NTIS)

This report, conducted by Raytheon Engineers & Constructor, was funded by the U.S. Trade and Development Agency. It examines the feasibility of a gas recovery project in the Bachaquero, Lagunillas, Machango, and Pueblo viejo Field in Venezuela. The report...

1999-01-01

405

Methodology for Evaluation of Feasibility: Multijurisdictional Urban Drainage and Flood Control Projects.  

National Technical Information Service (NTIS)

A methodology enabling engineers to evaluate the feasibility of urban drainage and flood control (UDFC) projects is reported. Currently, interest is increasing in nonstructural solutions to flooding. In addition to providing better land use plans and floo...

1977-01-01

406

Feasibility of Cogeneration Energy Supply for Oakland Airport Terminal Facilities: Consultant Report. Final Report.  

National Technical Information Service (NTIS)

The feasibility of using a cogeneration system at the Oakland Airport main terminal to provide electric power, heating, and cooling needs is evaluated. Both a reciprocating engine (Otto Cycle) or a combustion turbine (Brayton Cycle) were considered. Waste...

1980-01-01

407

Contaminant inputs to the Hudson-Raritan estuary  

SciTech Connect

Source locations and an estimate of the magnitude of contaminant inputs to the Hudson-Raritan Estuary are presented. The relative contribution of the various sources is indicated and data gaps are identified. Six sources of contaminant inputs were evaluated: nontidal tributary, municipal and industrial wastewater, atmospheric, urban runoff, accidental spills, and landfill leachate. The latter five sources were evaluated downstream of the tributary water quality stations, since sources above these points are reflected in the tributary inputs. In addition to flow or volume for each source, data on concentrations of conventional pollutants (solids, organic matter, nutrients, and bacterial indicators), organic toxics, and heavy metals were sought. A large quantity of data was obtained from numerous federal, state, county, and municipal agencies, and private firms. The data were analyzed to obtain average mass loads of specific contaminants into the Hudson-Raritan Estuary.

Mueller, J.A.; Gerrish, T.A.; Casey, M.C.

1982-08-01

408

Multibiomarker assessment of three Brazilian estuaries using oysters as bioindicators  

SciTech Connect

Oysters have been largely employed as bioindicators of environmental quality in biomonitoring studies. Crassostrea rhizophorae was selected to evaluate the health status of three estuarine areas impacted by anthropogenic activities along the Brazilian coast, in three estuarine complexes, ranging in latitude from 7 to 25 deg. S. In each estuary three sites were sampled in Winter and in Summer: a site considered as reference, and two sites next to contamination sources. Condition index was similar at all sites and estuaries, with the highest values found for Itamaraca oysters in Summer. Necrosis, hyperplasia, mucocyte hypertrophy and fusion of ordinary filaments were the main histopathological lesions observed. Muscle cholinesterase activity was overall similar, but with a strong seasonal effect. Inhibition or activation of branchial total ATPase and Na,K-ATPase activities at the contaminated sites was observed. The health status of these estuarine areas is quite similar, and the combined use of biomarkers is recommended.

Valdez Domingos, F.X. [Departamento de Biologia Celular, Universidade Federal do Parana. CP. 19031, CEP 81531-990, Curitiba, PR (Brazil)], E-mail: fa_valdez@yahoo.com; Azevedo, M. [Departamento de Fisiologia, Universidade Federal do Parana. CP. 19031, CEP 81531-990, Curitiba, PR (Brazil); Silva, M.D. [Departamento de Farmacologia, Universidade Federal do Parana. CP. 19031, CEP 81531-990, Curitiba, PR (Brazil); Randi, M.A.F. [Departamento de Biologia Celular, Universidade Federal do Parana. CP. 19031, CEP 81531-990, Curitiba, PR (Brazil); Freire, C.A. [Departamento de Fisiologia, Universidade Federal do Parana. CP. 19031, CEP 81531-990, Curitiba, PR (Brazil); Silva de Assis, H.C. [Departamento de Farmacologia, Universidade Federal do Parana. CP. 19031, CEP 81531-990, Curitiba, PR (Brazil); Oliveira Ribeiro, C.A. [Departamento de Biologia Celular, Universidade Federal do Parana. CP. 19031, CEP 81531-990, Curitiba, PR (Brazil)

2007-11-15

409

Modelling tidal currents in a sediment stratified idealized estuary  

NASA Astrophysics Data System (ADS)

A numerical modelling study on the effects of sediment-induced stratification on tidal currents is conducted for an idealized tidal estuary with a muddy seabed. The numerical model is a three-dimensional oceanic sediment transport model capable of predicting dynamics of Newtonian fluid mud layers due to coupling of the sea water density and suspended sediment concentration. The model uses a reparameterized bottom drag coefficient Cd that incorporates a linear stability function of flux Richardson number Rf. The study has shown that the sediment-induced stratification in the bottom boundary layer (BBL) reduces the vertical eddy viscosity and bottom shear stress in comparison with the model prediction in a neutrally stratified BBL. In response to these apparent reductions, the tidal current shear in the water column is increased in the estuary.

Wang, X. H.; Byun, D. S.; Wang, X. L.; Cho, Y. K.

2005-03-01

410

Effects of Prevailing Winds on Turbidity of a Shallow Estuary  

PubMed Central

Estuarine waters are generally more turbid than lakes or marine waters due to greater algal mass and continual re-suspension of sediments. The varying effects of diurnal and seasonal prevailing winds on the turbidity condition of a wind-dominated estuary were investigated by spatial and statistical analyses of wind direction, water level, turbidity, chlorophyll a, and PAR (Photosynthetically Active Radiation) collected in Lake Pontchartrain, Louisiana, USA. The prolonged prevailing winds were responsible for the long-term, large-scale turbidity pattern of the estuary, whereas the short-term changes in wind direction had differential effects on turbidity and water level in varying locations. There were temporal and spatial changes in the relationship between vertical light attenuation coefficient (Kd) and turbidity, which indicate difference in phytoplankton and color also affect Kd. This study demonstrates that the effect of wind on turbidity and water level on different shores can be identified through system-specific analyses of turbidity patterns.

Cho, Hyun Jung

2007-01-01

411

Heavy metals in sediment cores from a NW Spain estuary  

SciTech Connect

Core samples have been used to describe the chronology of heavy metal inputs to aquatic systems. Metal concentration profiles have been investigated to detect pollution, to establish when the polluting event started, and to quantify its magnitude relative to [open quotes]precivilization[close quotes] background values. Less frequently, and mainly in studies of coastal systems, the heavy metal nonresidual fraction has been measured to estimate the portion of trace metals potentially available for the biota or remobilization processes, and to assist in identifying the origin of metal inputs. This work is part of a wider study of metal concentrations in organisms and superficial sediments from a small estuary in NW Spain. The aims of this research were to detect any potential pollutant input to the sediments of the estuary, and to establish the influence of postdepositional redistribution on the heavy metal concentrations of oxidized surface sediments. 17 refs., 1 fig.

Barreiro, R.; Real, C.; Carballeira, A. (Universidad de Santiago de Compostela (Spain))

1994-09-01

412

Aircraft towing feasibility study. Final report  

SciTech Connect

Energy costs and availability are major concerns in most parts of the world. Many ways of increasing energy supply and reducing consumption are being proposed and investigated. One that holds considerable promise is the extended towing of aircraft between airport runways and terminal gate areas with engines shut down. This study provides a preliminary assessment of the constraints on and feasibility of extended aircraft towing. Past aircraft towing experience and the state-of-the-art in towing equipment are reviewed. Safety and operational concerns associated with aircraft towing are identified, and the benefits and costs of implementing aircraft towing at 20 major US airports are analyzed. It was concluded that extended aircraft towing is technically feasible and that substantial reductions in aircraft fuel consumption and air pollutant emissions can be achieved through its implementation. It was also concluded that, although capital and operating costs associated with towing would be increased, net savings could generally be attained at these airports. Because of the lack of past experience and the necessity of proving the cost effectiveness of the towing concept, a demonstration of the feasibility of large-scale aircraft towing is necessary. The study evaluates the suitability of the 20 study airports as potential demonstration sites and makes recommendations for the first demonstration project.

Not Available

1980-09-01

413

Types of saltwater intrusion of the Changjiang Estuary  

Microsoft Academic Search

The Changjiang Estuary is characterized by multi-order bifurcations, unsteady sub-merged sandbars, mid-channel sandbars, creeks\\u000a and riffles. The following four types of saltwater intrusion are found: (1) direct intrusion from the sea; (2) intrusion during\\u000a tidal flooding; (3) intrusion from tidal flats overflow; and (4) salt water coming upstream through other waterways. These\\u000a result in a complicated temporal and spatial salinity

Zhichang Mao; Huanting Shen; T. James Liu; D. Eisma

2001-01-01

414

Influence of the Deep Waterway Project on the Changjiang Estuary  

Microsoft Academic Search

Using the improved 3-D ECOM model with a high resolution grid and incorporating various dynamic factors, the impact of the\\u000a deep waterway project on the saltwater intrusion in the Changjiang Estuary was analysed. Salinity in the South Branch is shown\\u000a to be influenced by saltwater intrusion downstream and from spillage of brackish water from the North Branch upstream. In\\u000a the

Jianrong Zhu; Pingxing Ding; Liquan Zhang; Hui Wu; Huijiang Cao

415

Acidification of Lower St. Lawrence Estuary Bottom Waters  

Microsoft Academic Search

Accumulation of metabolic CO2 can acidify marine waters above and beyond the ongoing acidification of the ocean by anthropogenic CO2. The impact of respiration on carbonate chemistry and pH is most acute in hypoxic and anoxic basins, where metabolic CO2 accumulates to high concentrations. The bottom waters of the Lower St. Lawrence Estuary (LSLE), where persistently severe hypoxia has developed

Alfonso Mucci; Michel Starr; Denis Gilbert; Bjorn Sundby

2011-01-01

416

Nodical Modulation of Tides in Mixed Semi-diurnal Estuaries  

NASA Astrophysics Data System (ADS)

Mixed semi-diurnal tides and associated processes in estuaries and other coastal waters are substanially modulated by variations in lunar declination, which has a 27.21 day "nodical month" period, although these influences are generally ascribed to the more obvious changes in lunar phase, which varies with the 29.53 day synodical month. Analyses of archival sea level data, primarily in the San Francisco (California) Estuary, demonstrate previously undescribed patterns at a range of temporal scales. First, "ambiguous" high and low tides (neither HHW, LHW, HLW, nor LLW) recur in a consistent 13.61 day pattern of 1, 3, 5, or 7 adjacent ambiguous HW followed by 1 or 3 ambiguous LW. Thus, the dominant tidal current (LLW-HHW or HHW-LLW) of any mixed semi-diurnal estuary reverses every 13.61 days for a few days, with potentially dramatic influences on water body and sediment fluxes. Second, while the diurnal timing of HHW or LLW typically advances about 50 minutes each solar day, the "tidal pattern cross-over" resets the timing of HHW and LLW by 12.42 hours every 13.61 days, resulting in a strong apparent seasonality in the diurnal timing of tidal maxima and minima. This seasonality significantly controls the temporal and spatial distribution of processes influenced both by hydroperiod and temperature or solar insolation. Finally, while the resulting "seasonal" pattern is stable over short series of observations, it in fact reflects a 366.34 day pattern, which means that the seasonality itself has a 335 year period. Thus, coastal areas which are now generally flooded (HHW) at night in the summer and during the day in the winter had the opposite pattern about 170 years ago. This means that many century-scale physical and biotic changes in estuaries may be due to nodical tidal phenomena rather than solely to anthropogenic causes.

Malamud-Roam, K.

2001-12-01

417

Levels of tributyltin in sediments from Tagus estuary nature reserve  

Microsoft Academic Search

Concentrations of tributyltin in sediments from 9 selected stations located in the upper Tagus River estuary nature reserve,\\u000a Portugal, were determined. Tributyltin (TBT) concentrations in the sediments ranged from 5 to 35 ng g?1 on a dry weight basis. The persistent TBT contamination observed in the sediments from this important European ecosystem\\u000a is primarily related to shipping activities as well

J. M. F. Nogueira; B. Simplício; M. H. Floréncio; A. M. M. Bettencourt

2003-01-01

418

Planktonic fish eggs and larvae of sandy hook estuary  

Microsoft Academic Search

Twenty species of planktonic fish eggs and larvae were identified from 75 surface plankton tows made at river, bay, and ocean\\u000a locations in the Sandy Hook estuary. A gradual increase in the number of species through the spring to a peak in the summer\\u000a was followed by a decline in the fall and winter. Seventeen species were collected at a

Robert A. Croker

1965-01-01

419

Effects of wave forcing on a subterranean estuary  

NASA Astrophysics Data System (ADS)

Wave and tide are important forcing factors that typically coexist in coastal environments. A numerical study was conducted to investigate individual and combined effects of these forces on flow and mixing processes in a nearshore subterranean estuary. A hydrodynamic model based on the shallow water equations was used to simulate dynamic sea level oscillations driven by wave and tide. The oscillating sea levels determined the seaward boundary condition of the coastal aquifer, where variably saturated, variable density flow was modeled. The simulation results showed that waves induced an onshore upward tilt in the phase-averaged sea level (wave setup). The resulting hydraulic gradient generated pore water circulations in the nearshore zone of the coastal aquifer, which led to formation of an upper saline plume (USP) similar to that formed due to tides. However, mixing of recirculating seawater in the USP with underlying fresh groundwater was less intensive under the high-frequency wave oscillations. In the case of combined forcing, wave-induced circulations coupled with the intratidal flows strengthened the averaged, circulating pore water flows in the nearshore zone over the tidal period. The circulating flows increased exchange between the subterranean estuary and ocean, contributing 61% of the total submarine groundwater discharge for the simulated condition in comparison with the 40% and 49% proportions caused by the same but separate tidal and wave forcing, respectively. The combined forces also created a more extensive USP with the freshwater discharge zone shifted farther seaward. The freshwater flow paths in the intertidal subterranean estuary were modified with a significant increase in the associated transit times. The interplay of wave and tide led to increased mixing between discharging fresh groundwater and recirculating seawater. These results further demonstrate the complexity of nearshore groundwater systems and have implications for future investigations on the fate of land-sourced chemicals in the subterranean estuary prior to discharge to the ocean.

Xin, Pei; Robinson, Clare; Li, Ling; Barry, D. A.; Bakhtyar, R.

2010-12-01

420

Simulating the lateral transport of ichthyoplankton in the Potomac estuary  

Microsoft Academic Search

Previous simulations of potential ichthyoplankton entrainment by power generating stations on the Potomac estuary have not\\u000a included the influence of lateral transport in distributing eggs and larvae over the nursery area. Therefore, two-dimensional,\\u000a vertically-averaged hydrodynamic and kinematic models of passive organism transport were developed to represent advective\\u000a and dispersive processes near the proposed Douglas Point Nuclear Generating Station. Although the

Robert E. Ulanowicz; John M. Lindsay; William C. Caplins; Tibor T. Polgar

1982-01-01

421

Biological uptake of dissolved silica in the Amazon river estuary.  

PubMed

Approximately 25 percent of the dissolved silica carried by the Amazon River is depleted through diatom production in the inner estuary. Annual production of opaline frustules is estimated to be 15 million tons. However, few diatoms accumulate in modern shelf sediments and chemical recycling appears to be slight. Instead, many frustules apparently are transported landward into the river system, where they deposit in dunes and layers on and within mud and sand bars. PMID:17789156

Milliman, J D; Boyle, E

1975-09-19

422

A model of dynamics in the lower Potomac River Estuary  

Microsoft Academic Search

A simple two-dimensional numerical model has been developed to represent the observed vertical structure of tidal and nontidal\\u000a currents and tidal elevations along a reach of the lower Potomac River Estuary. The model is based on a linearized longitudinal\\u000a momentum equation and a laterally averaged continuity equation. It incorporates the effects of a naturally varying channel\\u000a cross-section through the continuity

Robert E. Wilson

1977-01-01

423

The circulation and salinity distribution of the Upper Potomac estuary  

Microsoft Academic Search

Salinity and current data from the Upper Potomac estuary have been analyzed to determine the intensity of the internal circulation.\\u000a One set of data, collected during the fall of 1973, suggested that a reverse flow existed as far upstream as Maryland Point.\\u000a Data taken during other periods indicated that an estuarine circulation, with a reverse flow in the lower layer,

A. J. Elliott

1976-01-01

424

Nontidal circulation and mixing processes in the lower Potomac estuary  

Microsoft Academic Search

An analysis of the vertical structure of nontidal longitudinal currents and salinity in a reach of the lower Potomac River\\u000a Estuary suggests that values for vertical eddy viscosity and eddy diffusivity scale with water depth H, tidal current amplitude\\u000a U and bulk Richardson number according to conventional empirical formulas. However, the constant which relates the vertical\\u000a eddy coefficients under conditions

Andrew D. Hamilton; Robert E. Wilson

1980-01-01

425

Estimates of advection and diffusion in the Potomac estuary  

Microsoft Academic Search

A two?layered dispersion model, suitable for application to partially?mixed estuaries, has been developed to provide hydro?logical interpretation of the results of biological sampling. The model includes horizontal and vertical advection plus both horizontal and vertical diffusion. A pseudo?geostrophic method, which includes a damping factor to account for internal eddy friction, is used to estimate the horizontal advective fluxes and the

A. J. Elliott

1976-01-01

426

Heavy metals on tidal flats in the Yangtze Estuary, China  

Microsoft Academic Search

Five short cores were used to examine heavy metals on tidal flats in the Yangtze Estuary, China. Statistically insignificant\\u000a trends in lead-210 and most metals with core depth are primarily due to high sedimentation rates. Metal contents are correlated\\u000a with percent aluminum, which reflects the clay contents in the sediment, and they are also affected by proximity to sewage\\u000a outlets

Z. Chen; R. Kostaschuk; M. Yang

2001-01-01

427

Toxicity of sediments and pore water from Brunswick Estuary, Georgia  

Microsoft Academic Search

A chlor-alkali plant in Brunswick, Georgia, USA, discharged >2 kg mercury\\/d into a tributary of the Turtle River-Brunswick\\u000a Estuary from 1966 to 1971. Mercury concentrations in sediments collected in 1989 along the tributary near the chlor-alkali\\u000a plant ranged from 1 to 27 ?g\\/g (dry weight), with the highest concentrations found in surface (0–8 cm) sediments of subtidal\\u000a zones in the

Parley V. Winger; Peter J. Lasier; Harvey Geitner

1993-01-01

428

Environmental public health surveillance: possible estuary-associated syndrome.  

PubMed Central

Public health surveillance involves the collection, analysis, and dissemination of data for use in public health practice. A surveillance system includes the capacity to collect and analyze data as well as the ability to disseminate the data to public health agencies that can undertake effective prevention and control activities. An emerging issue in environmental public health surveillance involves human exposure to the toxins produced by microorganisms present in oceans and estuaries. One of these organisms is Pfiesteria piscicida Steidinger & Burkholder, a dinoflagellate found in estuaries along the Atlantic and gulf coasts of the United States. There have been reports of both human illness associated with occupational exposures to concentrated laboratory cultures of P. piscicida and massive fill kills associated with the presence of the organism in rivers and estuaries. These reports, and anecdotal reports from people who worked on rivers where the organism has been found, generated concern that environmental exposures to P. piscicida, similar organisms, or perhaps a toxin or toxins produced by the organism(s), could cause adverse human health effects. To begin to evaluate the public health burden associated with P. piscicida, investigators from the National Center for Environmental Health at Centers for Disease Control and Prevention and health agencies from states along the Atlantic coast collaborated to develop a passive surveillance system for collecting, classifying, and tracking public inquiries about the organism. Specifically, the group developed exposure and symptom criteria and developed data collection and reporting capabilities to capture the human health parameters collectively referred to as possible estuary-associated syndrome (PEAS). The surveillance system was implemented in six states (Delaware, Florida, Maryland, North Carolina, South Carolina, Virginia) beginning in June 1998. From 1 June 1998 through 30 June 2001, the six state health agencies participating in the PEAS surveillance system received 3,859 calls: 3,768 callers requested information and 91 callers reported symptoms. Five individuals have been identified as meeting PEAS criteria.

Backer, L C; Niskar, A S; Rubin, C; Blindauer, K; Christianson, D; Naeher, L; Rogers, H S

2001-01-01

429

Benthic repopulation of the Raritan River estuary following pollution abatement  

Microsoft Academic Search

A total of 69 samples of benthic animals was taken in the lower 20 km of the Raritan River estuary from 1957 to 1960. During 1957, under heavily polluted conditions, no frcsh- water spccics wcrc discovered. Of the I7 marinc species found, the barnacle BaEanus im- prouisus extended 8.5 km above the river mouth; the remaining species were confined to

DAVID DEAN; HAROLD H. HASKIN

1964-01-01

430

Distribution of endocrine disruptors in the Mondego River estuary, Portugal  

Microsoft Academic Search

Recent studies in the Mondego River estuary demonstrated signs of pollution in the area, but the nature of the contamination\\u000a remains unexplored. Because there seems to be any studies in that zone checking for the simultaneous presence of xenoestrogenic\\u000a endocrine disrupting compounds, either of animal (estradiol and estrone), vegetal (daidzein, genistein and biochanin A), pharmaceutical\\u000a (17?-ethynylestradiol) or industrial (bisphenol A,

Cláudia Ribeiro; Miguel Ângelo Pardal; Filipe Martinho; Rui Margalho; Maria Elizabeth Tiritan; Eduardo Rocha; Maria João Rocha

2009-01-01

431

Rio Tinto estuary (Spain): 5000 years of pollution  

Microsoft Academic Search

Mining of massive sulfide deposits in southwestern Spain extending back to the Copper and Bronze Ages has resulted in the\\u000a pollution of the Rio Tinto fluvial-estuarine complex, the site of Columbus' departure for the New World in 1492. Additional\\u000a sources of potential pollution include the large industrial complex at Huelva near the lower portion of the estuary. Extensive\\u000a analysis of

R. A. Davis Jr.; A. T. Welty; J. Borrego; J. A. Morales; J. G. Pendon; Jeffrey G Ryan

2000-01-01

432

Counting on ?-diversity to safeguard the resilience of estuaries.  

PubMed

Coastal ecosystems are often stressed by non-point source and cumulative effects that can lead to local-scale community homogenisation and a concomitant loss of large-scale ecological connectivity. Here we investigate the use of ?-diversity as a measure of both community heterogeneity and ecological connectivity. To understand the consequences of different environmental scenarios on heterogeneity and connectivity, it is necessary to understand the scale at which different environmental factors affect ?-diversity. We sampled macrofauna from intertidal sites in nine estuaries from New Zealand's North Island that represented different degrees of stress derived from land-use. We used multiple regression models to identify relationships between ?-diversity and local sediment variables, factors related to the estuarine and catchment hydrodynamics and morphology and land-based stressors. At local scales, we found higher ?-diversity at sites with a relatively high total richness. At larger scales, ?-diversity was positively related to ?-diversity, suggesting that a large regional species pool was linked with large-scale heterogeneity in these systems. Local environmental heterogeneity influenced ?-diversity at both local and regional scales, although variables at the estuarine and catchment scales were both needed to explain large scale connectivity. The estuaries expected a priori to be the most stressed exhibited higher variance in community dissimilarity between sites and connectivity to the estuary species pool. This suggests that connectivity and heterogeneity metrics could be used to generate early warning signals of cumulative stress. PMID:23755252

de Juan, Silvia; Thrush, Simon F; Hewitt, Judi E

2013-06-05

433

Dissolved oxygen conditions in northern Gulf of Mexico estuaries  

USGS Publications Warehouse

Because deficient dissolved oxygen (DO) levels may have severe detrimental effects on estuarine and marine life, DO has been widely used as an indicator of ecological conditions by environmental monitoring programs. The U.S. EPA's Environmental Monitoring and Assessment Program for Estuaries (EMAP-E) monitored DO conditions in the estuaries of the Gulf of Mexico from 1991 to 1994. DO was measured in two ways: 1)instantaneous profiles from the surface to the bottom were taken during the day, and 2) continuous measurements were taken near the bottom at 15 min intervals for at least 12 h. This information was summarized to assess the spatial distribution and severity of DO conditions in these estuaries. Depending on the criteria used to define hypoxia (DO concentrations usually < 2 mg L-1 or 15 mg L-1) and the method by which DO is measured, we estimate that between 5.2 and 29.3% of the total estuarine area in the Louisianian Province was affected by low DO conditions.

Engle, V. D.; Kevin, Summers, J.; Macauley, J. M.

1999-01-01

434

Environmental contaminants in bald eagles in the Columbia River estuary  

SciTech Connect

Eggs, blood, and carcasses of bald eagles (Haliaeetus leucocephalus) and fish were collected and breeding success of eagles was monitored in the Columbia River estuary, 1980-87, to determine if contaminants were having an effect on productivity. High levels of dichloro diphenyl dichloroethylene (DDE), polychlorinated biphenyls (PCB's), and 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) were found in eggs, blood from adults, and 2 eagle carcasses. Detectable levels of DDE and PCB's were found in blood of nestlings indicating they were exposed to these contaminants early in life. Increasing concentrations of DDE and PCB's with age also indicated accumulation of these contaminants. Adult eagles also had higher levels of mercury (Hg) in blood than subadults or young indicating accumulation with age. The high levels of DDE and PCB's were associated with eggshell thinning ([bar x] = 10%) and with productivity ([bar x] = 0.56 young/occupied site) that was lower than that of healthy populations (i.e., [ge]1.00 young/occupied site). DDE and PCB's had a deleterious effect on reproduction of bald eagles in the estuary. The role dioxins play in eagle reproduction remains unclear, but concentrations in eagle eggs were similar to those in laboratory studies on other species where dioxins adversely affected hatchability of eggs. Probable source of these contaminants include dredged river sediments and hydroelectric dams, and the proper management of each may reduce the amount of contaminants released into the Columbia River estuary. 46 refs., 1 fig., 4 tabs.

Anthony, R.G.; Garrett, M.G. (Oregon State Univ., Corvallis (United States)); Schuler, C.A. (Fish and Wildlife Service, Portland, OR (United States))

1993-01-01

435

Digital flow model of the Chowan River estuary, North Carolina  

USGS Publications Warehouse

A one-dimensional deterministic flow model based on the continuity equation had been developed to provide estimates of daily flow past a number of points on the Chowan River estuary of northeast North Carolina. The digital model, programmed in Fortran IV, computes daily average discharge for nine sites; four of these represent inflow at the mouths of major tributaries, the five other sites are at stage stations along the estuary. Because flows within the Chowan River and the lower reaches of its tributaries are tidally affected, flows occur in both upstream and downstream directions. The period of record generated by the model extends from April 1, 1974, to March 31, 1976. During the two years of model operation the average discharge at Edenhouse near the mouth of the estuary was 5,830 cfs (cubic feet per second). Daily average flows during this period ranged from 55,900 cfs in the downstream direction on July 17, 1975, to 14,200 cfs in the upstream direction on November 30, 1974

Daniel, C. C.

1977-01-01

436

NOAA Estuary-of-the-Month Seminar Series No. 14. Lake Erie Estuarine Systems: Issues, Resources, Status, and Management.  

National Technical Information Service (NTIS)

Contents: Overview of Lake Erie and its estuaries within the Great Lakes ecosystem; Paleogeology and geomorphology; The effect of Lake Erie on its tributaries--resulting tributary transport mechanisms and contrasts with marine estuaries; Remote sensing of...

K. A. Krieger

1989-01-01

437

RELATIONS OF FISH AND SHELLFISH DISTRIBUTIONS TO HABITAT AND WATER QUALITY IN THE MOBILE BAY ESTUARY, USA  

EPA Science Inventory

The Mobile Bay estuary provides rich habitat for many fish and shellfish, including those identified as economically and ecologically important. The National Estuary Program has focused on restoration of degraded estuarine habitat on which these species depend. To support this ...

438

A feasibility study of a linear laser heated solenoid fusion reactor. Final report  

Microsoft Academic Search

This report examines the feasibility of a laser heated solenoid as a fusion or fusion-fission reactor system. The objective of this study, was an assessment of the laser heated solenoid reactor concept in terms of its plasma physics, engineering design, and commercial feasibility. Within the study many pertinent reactor aspects were treated including: physics of the laser-plasma interaction; thermonuclear behavior

1976-01-01

439

The offshore disposal of radioactive waste by drilled emplacement: A feasibility study  

Microsoft Academic Search

This book is a report, based on a study by Taylor Woodrow Construction Limited, on the overall feasibility of the disposal of high-level radioactive waste in boreholes drilled deep into the ocean bed. The work comprises an engineering appraisal of the disposal process with a view to establishing technical and operational feasibility and providing overall cost information to enable an

Bury

1985-01-01

440

Artiflcial Intelligence Technologies in Complex Engineering Design  

Microsoft Academic Search

Abstract: COMPUTATIONAL ENGINEERING AND DESIGN CENTERSCHOOL OF ENGINEERING SCIENCESDoctor of PhilosophyArtificial Intelligence Technologies in Complex Engineering Designby Yew Soon OngEngineering design optimization is an emerging technology whose application bothtends to shorten design-cycle time and finds new designs that are not only feasible,but also nearer to optimum, based on specified design criteria. Its gain in attentionin the field of complex designs

Yew Soon Ong

2002-01-01

441

Comparisons between the characteristics of ichthyofaunas in nearshore waters of five estuaries with varying degrees of connectivity with the ocean  

NASA Astrophysics Data System (ADS)

The characteristics of the fish faunas in nearshore, shallow (<1.2 m) waters of the basins of estuaries along the same coastline, but which were open to the ocean for varying periods, have been determined and compared. The fish faunas of the permanently-open Oyster Harbour, the seasonally-open Broke, Irwin and Wilson inlets and the normally-closed Wellstead Estuary on the south coast of Western Australia were sampled by seine net seasonally for 2 years. Irrespective of the frequency and duration that the estuary mouth was open, the ichthyofauna of each estuary was numerically dominated by three atherinid species and three gobiid species (92.9-99.7%), each of which completes its life cycle within these estuaries. The ichthyofaunal compositions of each estuary differed significantly, however, from that of each other estuary. These differences were largely attributable to the relative abundances of the above six species varying between estuaries, which, in turn, reflected differences in such factors as estuary mouth status, macrophyte cover and salinity. For example, Favonigobius lateralis and Leptatherina presbyteroides, which are also represented by marine populations, were most abundant in the permanently-open estuary (Oyster Harbour), which, in terms of substrate and salinity, most closely resembled the nearshore marine environment. In contrast, Leptatherina wallacei made its greatest contribution in the only estuary to exhibit a protracted period of greatly reduced salinities, which is consistent with its distribution in permanently-open estuaries on the lower west coast of Australia, while Atherinosoma elongata and Pseudogobius olorum were particularly numerous in estuaries containing dense stands of the seagrass Ruppia megacarpa. Marine species made the greatest contribution to species richness in the permanently-open estuary and least in the normally-closed estuary. Species richness was greatest in summer and least in winter in each estuary, but differed markedly between years only in Wilson Inlet. Density of fishes was greatest in the most eutrophic estuary (Wellstead Estuary) and least in the most oligotrophic estuary (Broke Inlet) and only underwent marked seasonal variations in Wilson Inlet and Wellstead Estuary, in which densities fell to their minima in winter. Ichthyofaunal composition varied between years in the Broke and Wilson inlets and Wellstead Estuary, in which there was little or no connection with the ocean in one of those years. Species composition underwent progressive seasonal changes throughout the year in Wellstead Estuary, due to the abundance of certain species peaking at different times of the year.

Hoeksema, S. D.; Chuwen, B. M.; Potter, I. C.

2009-10-01

442

Tribal Utility Feasibility Study  

SciTech Connect

The Schatz Energy Research Center (SERC) assisted the Yurok Tribe in investigating the feasibility of creating a permanent energy services program for the Tribe. The original purpose of the DOE grant that funded this project was to determine the feasibility of creating a full-blown Yurok Tribal electric utility to buy and sell electric power and own and maintain all electric power infrastructure on the Reservation. The original project consultant found this opportunity to be infeasible for the Tribe. When SERC took over as project consultant, we took a different approach. We explored opportunities for the Tribe to develop its own renewable energy resources for use on the Reservation and/or off-Reservation sales as a means of generating revenue for the Tribe. We also looked at ways the Tribe can provide energy services to its members and how to fund such efforts. We identified opportunities for the development of renewable energy resources and energy services on the Yurok Reservation that fall into five basic categories: • Demand-side management – This refers to efforts to reduce energy use through energy efficiency and conservation measures. • Off-grid, facility and household scale renewable energy systems – These systems can provide electricity to individual homes and Tribal facilities in areas of the Reservation that do not currently have access to the electric utility grid. • Village scale, micro-grid renewable energy systems - These are larger scale systems that can provide electricity to interconnected groups of homes and Tribal facilities in areas of the Reservation that do not have access to the conventional electric grid. This will require the development of miniature electric grids to serve these interconnected facilities. • Medium to large scale renewable energy development for sale to the grid – In areas where viable renewable energy resources exist and there is access to the conventional electric utility grid, these resources can be developed and sold to the wholesale electricity market. • Facility scale, net metered renewable energy systems – These are renewable energy systems that provide power to individual households or facilities that are connected to conventional electric utility grid.

Engel, R. A.; Zoellick, J. J.

2007-06-30

443

Rocket Engine Jet Blast Attenuation in Water.  

National Technical Information Service (NTIS)

The investigation was conducted to determine the feasibility of launching missiles and superboosters from overwater sites. Information is needed to predict the depth of liquid-propellant rocket engine exhaust gas penetration into water. Methods will be re...

G. W. Leese

1967-01-01

444

Modelling of tidal hydrodynamics for a tropical ecosystem with implications for pollutant dispersion (Cohin Estuary, Southwest India)  

Microsoft Academic Search

Tidal circulation in the Cochin Estuary, a moderately polluted estuary along the southwest coast of India, was studied using\\u000a a 2D hydrodynamic model. The predicted tides and currents showed very good agreement with measured tides. Particle trajectories\\u000a and residual currents computed from the model have been used to classify the study region into three zones: northern estuary,\\u000a central estuary, and

Kizhakkepat Kalathil Balachandran; Guddemmari Sidha Reddy; Chenicherry Revichandran; Kotamarpi Srinivas; Panachikkal Ramakrishnan Vijayan; Tony Joseph Thottam

2008-01-01

445

Engineering TV  

NSDL National Science Digital Library

Introducing Engineering TV, an innovative online video program by engineers for engineers. Twice a week, each 5-8 minute episode shows cutting-edge technology in action and looks behind the scenes as today's engineers shape tomorrow's breakthroughs.

2010-04-14

446

Dissolved inorganic nutrients and chlorophyll A in an estuary receiving sewage treatment plant effluents: Cachoeira River estuary (NE Brazil).  

PubMed

Sampling was conducted monthly during a transition period between the dry and rainy seasons in order to evaluate the effectiveness of a municipal sewage treatment plant (STP) in eutrophication control. STP effluent and fluvial input data were also estimated. In the dry period, high concentrations of nutrients, chlorophyll a (up to 360 ?g?L(-1)), and anoxia in bottom waters were observed in the upper portion of the estuary. Nitrate was scarce during the dry months, although high concentrations were observed at the river sources and the upper estuary. The N:P and Si:P molar ratios were usually below 16:1, and the Si:N ratio was higher than 1:1. The fluvial inputs were a greater source of nutrients to the estuary than the STP, but nutrient loading by these effluents were also important in contributing to the eutrophication of the upper estuarine zone, especially in the dry season when symptoms were more intense. PMID:23179722

Silva, Maria Aparecida Macêdo; Eça, Gilmara Fernandes; Santos, Danielle Felix; Guimarães, Alonso Góes; Lima, Michelle Coêlho; de Souza, Marcelo Friederichs Landim

2012-11-24

447

Valuing environmental water pulses into the Incomati estuary: Key to achieving equitable and sustainable utilisation of transboundary waters  

Microsoft Academic Search

Upstream developments in the Incomati river basin, shared by South Africa, Swaziland and Mozambique, have altered downstream flows significantly. The frequency of small floods into the estuary has been reduced dramatically. This change in the flow regime has impacted on the state of the environment downstream, and the Incomati estuary in particular. The estuary requires fresh water pulses that naturally

D. José Sengo; Albert Kachapila; Pieter van der Zaag; Marloes Mul; Sakhiwe Nkomo

2005-01-01

448

A review of land–sea coupling by groundwater discharge of nitrogen to New England estuaries: Mechanisms and effects  

Microsoft Academic Search

Hydrologists have long been concerned with the interface of groundwater flow into estuaries, but not until the end of the last century did other disciplines realize the major role played by groundwater transport of nutrients to estuaries. Mass balance and stable isotopic data suggest that land-derived NO3, NH4, and dissolved organic N do enter estuaries in amounts likely to affect

J. L. Bowen; K. D. Kroeger; G. Tomasky; W. J. Pabich; M. L. Cole; R. H. Carmichael; I. Valiela

2007-01-01

449

Invaders eating invaders: exploitation of novel alien prey by the alien shimofuri goby in the San Francisco Estuary, California  

Microsoft Academic Search

The shimofuri goby (Tridentiger bifasciatus), which is native to Asian estuaries, was recently introduced to the San Francisco Estuary, California, USA. We conducted gut content analyses to examine the goby’s feeding ecology in this highly invaded estuary. Shimofuri gobies were generalist predators on benthic invertebrates, consuming seasonally abundant prey, especially amphipods (Corophium spp.). In addition, shimofuri goby utilized two novel

Scott A. Matern; Larry R. Brown

2005-01-01

450

The Future of Fish in Response to Large-Scale Change in the San Francisco Estuary, California  

Microsoft Academic Search

The San Francisco Estuary is the largest estuary on the west coast of North America and one of the most altered . It supports a diverse fish fauna in which key species are in severe decline . T he estuary is faced with catastrophic structural and ecological changes, especially in the Sacramento-San Joaquin Delta and Suisun Marsh, as the result

PETER B. MOYLE

2008-01-01

451

Geochemical sources, deposition and enrichment of heavy metals in short sediment cores from the Pearl River Estuary, Southern China  

Microsoft Academic Search

The Pearl River Estuary (PRE) is the largest estuary in the Southern China. Four short sediment cores (45–60cm long) recovered within the PECAI project from the estuary have been analyzed for grain size and geochemistry to reveal geochemical source and deposition environment and to assess enrichment and pollution of heavy metals in the sediments. Four geochemical sources were identified as

Shi Qi; Thomas Leipe; Peter Rueckert; Zhou di; Jan Harff

2010-01-01

452

E-estuary: A Decision Support System for Coastal Water and Ecosystem Management in the US (CZ09)  

EPA Science Inventory

Ready access to geographic information is needed to support management decisions for estuaries at local, state, regional, and national scales. The U.S. Environmental Protection Agency (US EPA) is developing e-Estuary, a decision-support system for coastal management. E-Estuary ...

453

E-Estuary: Developing a Decision Support System for Coastal Management in the Conterminous United States (IAHR)  

EPA Science Inventory

Ready access to geographic information is needed to support management decisions for estuaries at local, state, regional, and national scales. The U.S. Environmental Protection Agency (US EPA) is developing e-Estuary, a decision-support system for coastal management. E-Estuary ...

454

Assessment of changes to saltwater\\/freshwater habitat from reductions in flow to the Richmond River estuary, Australia  

Microsoft Academic Search

The Australian climate is highly variable and many Australian estuaries lack a seasonal pattern of freshwater flow. During periods of low freshwater inflow, saline waters enter from the ocean through the estuary mouth. These saline waters enter as density currents or as a result of tidal mixing. During periods of high freshwater inflow from the estuary catchment, salt water is

W. L. Peirson; R. Nittim; M. J. Chadwick; K. A. Bishop; P. R. Horton

2001-01-01

455

Coastal Estuaries as Habitat for a Freshwater Fish Species: Exploring Population-Level Effects of Salinity on Largemouth Bass  

Microsoft Academic Search

Estuaries are systems where marine and freshwaters interface. The largemouth bass Micropterus salmoides is a freshwater predator commonly found in the oligohaline portions of estuaries in coastal North America. As a popular recreational sport fish in estuaries, largemouth bass are caught in large numbers, but large (?2.3-kg) individuals are rarer than in inland (freshwater) systems. A pervasive factor affecting estuarine

Alicia J. Norris; Dennis R. DeVries; Russell A. Wright

2010-01-01

456

ECOLOGICAL CONDITION OF THE U.S. MID-ATLANTIC ESTUARIES: THE MID-ATLANTIC INTEGRATED ASSESSMENT (MAIA)  

EPA Science Inventory

The Mid-Atlantic Integrated Assessment (MAIA-Estuaries) evaluated ecological conditions in US Mid-Atlantic estuaries during the summers of 1997 and 1998. Over 800 probability-based stations were monitored in four main estuarine systems?Chesapeake Bay, the Delaware Estuary, Maryla...

457

Wind?wave development across a large shallow intertidal estuary: A case study of Manukau Harbour, New Zealand  

Microsoft Academic Search

Locally generated wind?waves in estuaries play an important role in the sediment dynamics and the transport of biota. Wave growth in estuaries is complicated by tidally varying depth, fetch, and currents. Wave development was studied at six sites along a transect across Manukau Harbour, New Zealand, which is a large intertidal estuary with a tidal range of up to 4

Murray J. Smith; Craig L. Stevens; Richard M. Gorman; John A. McGregor; Cameron G. Neilson

2001-01-01

458

Economic analysis of gas engine driven air compressors  

Microsoft Academic Search

The objective of this research is to conduct a feasibility study of gas engine driven air compressors versus electric motor driven air compressors. The methodology adopted in achieving this objective was to develop a linear equation, which was used to develop payback graphs. These graphs were used for the feasibility study. It was concluded that investing in engine driven air

N. R. Chedella; J. B. Wong-Kcomt; W. C. Turner

1993-01-01

459

Value Engineering  

Microsoft Academic Search

This paper defines value engineering, shows why it is necessary, and emphasizes the engineer's responsibility for using engineering disciplines in the design of a product. Recognizing that value engineering is a duty of the professional engineer, the paper stresses application of value engineering to attain Armed Services goals, and reduce costs while speeding up delivery of the weapon system. Many

A. Zappacosta

1962-01-01

460

Engine system assessment study using Martian propellants  

NASA Astrophysics Data System (ADS)

A feasibility study was performed that identified and characterized promising chemical propulsion system designs that utilize two or more of the propellant combinations: LOX/H2, LOX/CH4 and LOX/CO. The engine systems examined focused on the usage of common subsystem/component hardware where feasible. From the evaluation baseline employed, tripropellant MTV LOX cooled and bipropellant LEV and MEV engine systems are identified.

Pelaccio, D.; Jacobs, M.; Collins, J.; Scheil, C.; Meyer, M.

1992-07-01

461

On the use by birds of intertidal areas of the Tagus estuary: implications for management  

Microsoft Academic Search

The use of intertidal areas of the Tagus estuary by birds was re-analysed, based on data from 1990 to 1993, to describe (i) the temporal and spatial patterns of use of intertidal areas, (ii) the diet of birds during winter and (iii) the habitat selection patterns of feeding birds, during winter. The most common birds in the estuary were gulls,

Francisco Moreira

1999-01-01

462

Sediment source identification and residence times in the Maroochy River estuary, southeast Queensland, Australia  

NASA Astrophysics Data System (ADS)

Identification of sediment sources and associated nutrients and contaminants is crucial to the ecological management of aquatic systems. A combination of geochemical and radionuclide tracing techniques and geostatistical modelling have been used to determine the primary source areas of fine sediment delivered to the Maroochy River estuary. The application of radionuclide (137Cs and 210Pb) techniques indicate that approximately 70% of the sediment in the Maroochy River estuary originates from subsoil erosion. An average of 60% of sediment in the lower estuary originates from soils developed on the Landsborough Sandstone, with 35% coming from soils developed on granitoids. In the mid-Maroochy River estuary major contributions of fine sediment come from soils developed on Landsborough Sandstone (38%) and granitoids (36%). Estimated sediment residence times in the Maroochy River estuary are generally less than 30 years, however, one sample site near the estuary mouth had an estimated residence time of at least 30 years. This indicates that sediment accumulation rates in mangroves along the estuary margins are relatively low. Results from this study will be used by catchment managers to better target remedial action to reduce fine sediment delivery to the Maroochy River estuary.

Douglas, G.; Caitcheon, G.; Palmer, M.

2009-04-01

463

Valuing Estuarine Resource Services Using Economic and Ecological Models: The Peconic Estuary System Study  

Microsoft Academic Search

This article summarizes four integrated economic studies undertaken to contribute to resource preservation and restoration decisions for the Peconic Estuary System of Suffolk County, NY. Completed as part of the National Estuary Program, the studies apply distinct resource valuation methods to a wide range of resource issues. The principal goals of this article are to highlight different methodologies that may

Robert J. Johnston; Thomas A. Grigalunas; James J. Opaluch; Marisa Mazzotta; Jerry Diamantedes

2002-01-01

464

Dissolved manganese in the columbia river estuary: production in the water column  

Microsoft Academic Search

A chemical sensor was deployed as part of a package of instruments to develop a highly resolved picture of dissolved Mn and related parameters in the Columbia River estuary. The vertical distribution of dissolved Mn in the main channel shows a distinct middepth maximum of 10 to 15 nM. The maximum occurs at the same depth throughout the estuary, cutting

G. P. Klinkhammer; J. McManus

2001-01-01

465

Links between saltwater intrusion and subtidal circulation in the Changjiang Estuary: A model-guided study  

Microsoft Academic Search

In this paper we discuss the links between saltwater intrusion and subtidal circulation in the Changjiang Estuary based on a 3D numerical model. We restricted our study mainly to the three major outlets of the estuary: the South Passage, the North Passage, and the North Channel. Subtidal transport is landward in the South Passage and NNW- or NW-ward on the

Hui Wu; Jianrong Zhu; Byung Ho Choi

2010-01-01

466

Changes in biodiversity of the extremely polluted Golden Horn Estuary following the improvements in water quality  

Microsoft Academic Search

Long-term biological data supported by physicochemical parameters were evaluated to investigate the biodiversity of the Golden Horn Estuary from the past to the present. Limited observations dating back to 60years ago indicated the existence of a diverse community in this small estuary. Unfortunately, in parallel with the increase in unplanned settlements and industry around the Golden Horn, pollution stress increased

Ahsen Yüksek; Erdo?an Oku?; ?. Noyan Yilmaz; Asl? Aslan-Yilmaz; Seyfettin Ta?

2006-01-01

467

Birds of the Severn Estuary and Bristol Channel: Their current status and key environmental issues  

Microsoft Academic Search

The Severn Estuary and Bristol Channel encompass a number of designated sites supporting populations of waterbirds and seabirds that are of national or international importance, including the Severn Estuary and Burry Inlet Special Protection Areas (SPAs)\\/Ramsar Sites and Carmarthen Bay, the UK’s first marine SPA. Here, we provide an overview of the present numbers and trends of the waterbirds and

N. H. K. Burton; A. J. Musgrove; M. M. Rehfisch; N. A. Clark

2010-01-01

468

Distribution Patterns of Migratory Striped Bass in Plum Island Estuary, Massachusetts  

Microsoft Academic Search

This is the first study to assess how the coastal migratory stock of striped bass (Morone saxatilis) uses non-natal New England estuaries during their foraging migration. Using hydroacoustic telemetry from June through October in Plum Island Estuary, Massachusetts, I examined how long coastal migratory striped bass stayed throughout the seasons, if they were equally distributed, if individual striped bass were

Sarah M Pautzke

2008-01-01

469

Seasonal Use of a New England Estuary by Foraging Contingents of Migratory Striped Bass  

Microsoft Academic Search

Using acoustic telemetry on migratory striped bass Morone saxatilis in Plum Island Estuary (PIE), Massachusetts, we found that striped bass (335–634 mm total length) tagged in the spring and summer of 2005 (n = 14) and 2006 (n = 46) stayed in the estuary for an average of 66.0 d in 2005 and 72.2 d in 2006. Striped bass spent

Sarah M. Pautzke; Martha E. Mather; John T. Finn; Linda A. Deegan; Robert M. Muth

2010-01-01

470

Response of sand dunes to variations in tidal flow: Fraser Estuary, Canada  

Microsoft Academic Search

The morphology of dunes in rivers and estuaries often lags behind changes in river discharge and neap-spring tides. This study extends previous research by examining the response of large subtidal dunes in the Fraser Estuary, Canada, to changing flow conditions over a semidiurnal tidal cycle. An acoustic Doppler current profiler (ADCP) is used to measure three-dimensional velocity profiles and estimate

Ray Kostaschuk; Jim Best

2005-01-01

471

Episodic High Intensity Mixing Events in a Subterranean Estuary: Effects of Tropical Cyclones  

Microsoft Academic Search

Hydrostatic balances between fresh and saline groundwater and saline surface water control the physical and chemical framework of subterranean estuaries, but they are responsive to high frequency (waves and tides), low frequency (seasonal recharge patterns), and episodic (storm) events. In this study, we document a salinity and pressure perturbation to the subterranean estuary in east-central Florida during and after the

Christopher G. Smith; Jaye E. Cable; Jonathan B. Martin

2008-01-01

472

Discovery of introduced and cryptogenic cochliopid gastropods in the San Francisco Estuary, California  

Microsoft Academic Search

We report the first discovery in the San Francisco Estuary ('Estuary') of two cochliopid gastropods, Littoridinops monroensis and Tryonia porrecta. These identifications were based on morphological criteria and supported by analysis of mitochondrial DNA (cytochrome c oxidase subunit I, COI) sequence data. We also report the first discovery of males in parthenogenetic T. porrecta. The new records rep- resent large

ROBERT HERSHLER; CHERYL L. DAVIS; CHRISTOPHER L. KITTING; HSIU-PING LIU

2007-01-01

473

Dissolved oxygen dynamics in a eutrophic estuary, Upper Newport Bay, California  

Microsoft Academic Search

Eutrophication often causes hypoxia in estuarine and coastal systems, but the mechanisms that control hypoxic events vary among estuaries and are often difficult to discern. We monitored surface and bottom dissolved oxygen (DO) in the Upper Newport Bay (UNB), a tidally mixed estuary in southern California subject to anthropogenic nutrient loading, eutrophication and hypoxia. Our goal was to identify the

Nikolay P. Nezlin; Krista Kamer; Jim Hyde; Eric D. Stein

2009-01-01

474

PRELIMINARY REPORT ON THE ARCHAEOLOGY AND PALEOECOLOGY OF THE ABALONE ROCKS ESTUARY, SANTA ROSA ISLAND, CALIFORNIA  

Microsoft Academic Search

Although California's mainland coast was once punctuated by numerous large embayments, estuaries are rare or absent on the Channel Islands. Recent archaeological and paleoecological research, however, confirm the presence of an estuary near Abalone Rocks, Santa Rosa Island. Preliminary survey and small-scale excavations suggest that early island peoples harvested shellfish (e.g., venus clams (Chione spp.), Washington clam (Saxidomas nuttalli), California

TORBEN C. RICK; DOUGLAS J. KENNETT; JON M. ERLANDSON

475

Coupling between the California Current System and a coastal plain estuary in low riverflow conditions  

Microsoft Academic Search

Willapa Bay, a partially mixed coastal plain estuary, is located on the shoreward side of a narrow, deep continental shelf whose water properties fluctuate on several day scales in response to alternating periods of upwelling and downwelling. Hydrographic surveys as well as water property and velocity time series at a number of sites both within the estuary and on the

B. M. Hickey; X. Zhang; N. Banas

2002-01-01

476

Chemical Indicators of Anthropogenic Nitrogen-Loading in Four Pacific Estuaries  

Microsoft Academic Search

Watershed inputs of anthropogenic nitrogen (N) are altering the trophic status of estuaries worldwide. In this study we compared two chemical approaches for assessing watershed N inputs to estuaries: (1) use of conventional nutrient concentration measurements, and (2) use of nitrogen isotope (o 15 N) measurements in estuarine sediments and biota. Of special interest was testing whether 015N assays were

Brian Fry; Arian Gace; James W. McClelland

2003-01-01

477

Impact of tide-induced residual currents on the salinity distribution around the Changjiang Estuary  

Microsoft Academic Search

Abstract: Changjiang is one of the largest rivers in the world. It has a complicated estuary, with four major outlets facing the East China Sea, i.e. the North Branch, North Channel, North Passage and the South Passage. Saltwater intrusion changes the pattern of hydrodynamics and sedimentation in this estuary, and the freshwater extension off the river mouth deeply influences the

H. Wu

2010-01-01

478

Changes in landscape pattern of wetlands in the Pearl Rivers Estuary in the past two decades  

Microsoft Academic Search

The Pearl River Estuary, which is an important relay station and wintering area for waterfowls, is rich in a variety of wetlands resource. However, in recent decades, the industrialization and urbanization in the Pearl River Estuary had been developing rapidly, which changed the wetland landscape there dramatically. In this paper, based on remote sensing (RS) and geographic information system (GIS),

Xu Lang; Chen Xiaoxiang; Li Xiaolan; He Zhijian

2009-01-01

479

Trace Elements and Radionuclides in the Connecticut River and Amazon River Estuary.  

National Technical Information Service (NTIS)

The Connecticut River, its estuary, and the Amazon River estuary were studied to elucidate some of the processes which control river water chemistry and the flux of elements to the sea. The approach taken was to identify inputs to the Connecticut River an...

E. P. Dion

1983-01-01

480

Second international symposium on the biogeochemistry of model estuaries: Estuarine processes in global change  

SciTech Connect

This report consists of abstracts of papers presented at the symposium of Biogeochemistry. The main topics discussed at the meeting are; nutrient and mineral cycling, trace element distribution, sources and sinks of estuaries, sedimentation, importance of organic matter, and other biogeochemical processes of estuaries.

Not Available

1991-12-31

481

Water quality and ecological status of the Alcantara River estuary (Italy)  

Microsoft Academic Search

The Alcantara River estuary was studied to obtain the first data on both water quality and ecological status of the only River Park in Sicily (Italy). Water samples were seasonally collected from three selected stations in the estuarine area and from one station at the mouth of the estuary in the marine coastal zone. Picoplankton and picophytoplankton counts were among

Concetta Gugliandolo; Valeria Lentini; Maria T. Fera; Erminia La Camera; Teresa L. Maugeri

482

DEVELOPING NUTRIENT CRIETERIA FOR ESTUARIES WITH VARIABLE OCEAN INPUTS: AN EXAMPLE FROM THE PACIFIC NORTHWEST  

EPA Science Inventory

Estuaries in the Pacific Northwest have major intraannual and within estuary variation in sources and magnitudes of nutrient inputs. To develop an approach for setting nutrient criteria for these systems, we conducted a case study for Yaquina Bay, OR based on a synthesis of resea...

483

Concentration and Distribution of Hydrophobic Organic Contaminants and Metals in the Estuaries of Ukraine  

EPA Science Inventory

In this baseline study of Ukrainian estuaries, sediments and organisms from the Dnieper and Boh estuaries and Danube Delta on the mainland, Sevastopol and Balaklava Bays on the Crimean Peninsula, and coastal Black Sea along the Crimean Peninsula were collected in 2006. Contamina...

484

Quaternary sedimentation in a tide-dominated estuary, northern New England  

Microsoft Academic Search

Northern New England is characterized by rocky shorelines frequently interrupted by linear embayments or estuaries. In contrast to more commonly studied coastal plain estuaries further south, these embayments often have relatively limited fluvial sediment supply, are affected by ice, and are strongly influenced by bedrock geology. High resolution subbottom seismics, sidescan sonar, surficial sediment sampling and gravity coring were conducted

1993-01-01

485

Importance of seagrass as a carbon source for heterotrophic bacteria in a subtropical estuary (Florida Bay)  

Microsoft Academic Search

A stable carbon isotope approach was taken to identify potential organic matter sources incorporated into biomass by the heterotrophic bacterial community of Florida Bay, a subtropical estuary with a recent history of seagrass loss and phytoplankton blooms. To gain a more complete understanding of bacterial carbon cycling in seagrass estuaries, this study focused on the importance of seagrass-derived organic matter

Clayton J. Williams; Rudolf Jaffé; William T. Anderson; Frank J. Jochem

2009-01-01

486

Demonstration and Hands-on Exercises with the Estuary Data Mapper  

EPA Science Inventory

The U.S. Environmental Protection Agency (US EPA) is developing e-Estuary, a decision-support system for applications of the Clean Water Act in coastal management. E-Estuary has three elements: an estuarine geo-referenced relational database, watershed GIS coverages, and tools t...

487

Genetic and meristic variations in the mummichog Fundulus heteroclitus, living in polluted and reference estuaries  

Microsoft Academic Search

Genetic and meristic variations were assessed in mummichogs (Fundulus heteroclitus) living in two sites downstream from a bleached kraft pulp mill in the Miramichi Estuary (Miramichi E.) (New Brunswick, Canada) and in four reference estuaries. Genetic variability detected by electrophoresis of enzymes was low except for EST-3. Geographic distribution of rare alleles at four loci, discontinuity in allelic frequencies at

S. Kirchhoff; J. M. Sévigny; C. M. Couillard

1999-01-01

488

A laboratory investigation into shear-generated mixing in a salt wedge estuary  

Microsoft Academic Search

The combination of strong density stratification and energetic forcing from tide and mean flows leads to complex circulation and exchange processes in estuaries. The present study was motivated by field results in the Valdivia Estuary, Chile, and others where a dramatic difference in salinity stratification was observed between low and high tides, believed to be attributable to the interacting roles

N. J. Grigg; G. N. Ivey

1997-01-01

489

The relationship between dissolved humic acids and soluble iron in estuaries  

NASA Astrophysics Data System (ADS)

Dissolved humic acid and soluble iron appear to be chemically unassociated in estuaries despite their coincident removal. This conclusion is supported by differences in the aggregation kinetics of soluble iron and dissolved humic acid, the inability of extracted humic acid to stabilize laboratory preparations of ferric hydroxide, and decreasing ratios of humic acid carbon to soluble iron along the axes of some estuaries.

Fox, L. E.

1984-04-01

490

Liver oxidative stress of the grey mullet Mugil cephalus presents seasonal variations in Ennore estuary.  

PubMed

The objective of this study was to determine the liver oxidative stress status of grey mullets living in heavy-metal-rich polluted Ennore estuary compared with unpolluted Kovalam estuary. Fish were collected from both estuaries during the monsoon and summer seasons from October 2004 to September 2006. Fish liver homogenate (N = 20 per group) was prepared for evaluating oxidative stress parameters. Fish living in the polluted estuary had significantly higher lipid oxidation products, conjugated dienes (0.346 +/- 0.017 vs 0.141 +/- 0.012 DA233/mg protein), lipid hydroperoxides (0.752 +/- 0.032 vs 0.443 +/- 0.03 nmol/mg protein), and lipid peroxides (3.447 +/- 0.14vs 1.456 +/- 0.096 nmol MDA/mg protein) than those of the unpolluted estuary during the summer. In contrast, significantly lower levels of superoxide dismutase (20.39 +/- 1.14 vs 53.63 +/- 1.48 units/mg protein) and catalase (116 +/- 6.87vs 153 +/- 8.92 units/mg protein) were detected in the liver of fish from the polluted estuary (Ennore) compared to fish from the unpolluted estuary (Kovalam) during the summer. Variations in most of the oxidative stress parameters were observed between the summer and monsoon seasons, indicating the importance of seasonal variation for estuaries and their inhabitants. PMID:18853043

Padmini, E; Vijaya Geetha, B; Usha Rani, M

2008-10-03

491

Biochemical components in suspended particles and colloids: carbohydrates in the Potomac and Patuxent Estuaries  

Microsoft Academic Search

Carbohydrates were measured in suspended particles (> 0.4 ?m) and colloids over a 187 km segment of the Potomac Estuary and during a summer dinoflagellate bloom in the Patuxent Estuary (U.S.A.). The average carbohydrate composition of suspended particles was 43 ± 18% glucose, 13 ± 7% galactose, 11 + 4% rhamnose, 9 ± 4% fucose, 9 ± 4% xylose, 9

Anne C. Sigleo

1996-01-01

492

Spatial distributions of pollen in surface sediments of the Potomac estuary  

Microsoft Academic Search

Pollen of trees extracted from surface sediments of the Potomac estuary represent all com- ponents of the arboreal vegetation, with the exception of Liriodendron tuZipiJeru (tulip pop- lar), and reflect the major forest gradients in a broad band adjacent to the estuary. Pollen of common trees restricted to the upper watershed, 60 km upstream of the limit of tidal influ-

GRACE S. BRUSH; RUTH S. DEFRIES

1981-01-01

493

Excessive nutrients select for dinoflagellates in the stratified Patapsco River estuary: Margalef reigns  

Microsoft Academic Search

Phytoplankton composition in the mesohaline Patapsco River estuary, a tributary of Chesapeake Bay, is dominated by dinoflagellates throughout the summer. This dominance is attrib- uted to the nutrient-turbulence relationships that have been described by Margalef over the last 30 yr, a field verification of this highly respected theory. The partially stratified estuary is typified by ambient nutrient concentrations higher than

K. G. Sellner; S. G. Sellner; R. V. Lacouture; R. E. Magnien

2001-01-01

494

Estimates of flushing times, submarine groundwater discharge, and nutrient fluxes to Okatee Estuary, South Carolina  

Microsoft Academic Search

A physical model based on determining the fraction of the tidal prism that returns to the estuary on the next high tide is used to estimate the flushing time of the Okatee River estuary. The return flow factor (b) of 0.81 yields a flushing time of 2 days. A mass balance model of 228Ra and salinity is also used to

Willard S. Moore; Jackson O. Blanton; Samantha B. Joye

2006-01-01

495

Fish and macro-crustacean communities and their dynamics in the Severn Estuary  

Microsoft Academic Search

The species of fish and macro-crustacean living within the Severn Estuary are reviewed. The fish community is notably species rich and exceeds 100 species in total for the estuary. Standardised long-term sampling at Hinkley Point in Bridgwater Bay gives a total complement of 83 for a single locality and this number is increasing by about one new species every two

P. A. Henderson; D. J. Bird

2010-01-01

496

RESPONSE OF GULF COAST ESTUARIES TO NUTRIENT LOAD: DISSOLVED OXYGEN DEPLETION  

EPA Science Inventory

GED has developed a process-based approach to hypoxia research on Pensacola Bay as a model Gulf of Mexico estuary. We selected Pensacola Bay because, like many Gulf coast estuaries, it is shallow, microtidal, and experiences seasonal hypoxia. We also have an historical database ...

497

STABLE ISOTOPE VARIATIONS IN SUSPENDED PARTICLES IN A TEMPERATE NORTH PACIFIC ESTUARY, OREGON, USA  

EPA Science Inventory

Spatial distributions of 13C and 15N in suspended particles were examined monthly over an annual cycle in the euphotic zone (0.5m) of the Yaquina River and Estuary, Oregon. Suspended organic matter in estuaries is a mixture of land-derived and oceanic carbon and nitrogen. In a...

498

River discharge, sediment transport and exchange in the Tana Estuary, Kenya  

Microsoft Academic Search

This study focuses on sediment transport and exchange dynamics in the 27km2 Tana Estuary located at Kipini in the north Kenya coast. The estuary is drained by the Tana River, which contributes more than 50% of the total river discharges into the Kenyan sector of the Indian Ocean. The study involved measurement of river discharges, estuarine flood–ebb tidal discharges, total

J. U. Kitheka; M. Obiero; P. Nthenge

2005-01-01

499

Water pollution in estuaries and coastal zones. (Latest citations from the NTIS bibliographic database). Published Search  

SciTech Connect

The bibliography contains citations concerning the studies of water pollution in estuaries and coastal zones. Citations examine the development, management, and protection of estuary and coastal resources. Topics include pollution sources, environmental monitoring, water chemistry, eutrophication, models, land use, government policy, and laws and regulations. (Contains 50-250 citations and includes a subject term index and title list.) (Copyright NERAC, Inc. 1995)

NONE

1996-02-01

500

Sea ice, hydrological, and biological processes in the Churchill River estuary region, Hudson Bay  

Microsoft Academic Search

A conceptual scheme for the transition from winter to spring is developed for a small Arctic estuary (Churchill River, Hudson Bay) using hydrological, meteorological and oceanographic data together with models of the landfast ice. Observations within the Churchill River estuary and away from the direct influence of the river plume (Button Bay), between March and May 2005, show that both

Z. A. Kuzyk; R. W. Macdonald; M. A. Granskog; R. K. Scharien; R. J. Galley; C. Michel; D. Barber; G. Stern

2008-01-01